Details from the National Weather Service
* WHAT...Temperatures as low as 35 will result in frost formation. * WHERE...Portions of northern Indiana and northwest Ohio. * WHEN...From 1 AM EDT /midnight CDT/ to 9 AM EDT /8 AM CDT/ Monday. * IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered. Take steps now to protect tender plants from the cold.
Forecast for the Somerset station issued Sun Oct 18, 6:45 PM
Four global weather models (GFS, ECMWF, ICON and GEM) are averaged, then corrected with this station's own record: how each kind of day and night has actually turned out here. The ± after each number is an 80% range: four times out of five, the actual temperature lands inside it. It is wider when the models disagree. How it works and how accurate it is.
The forecast in words
Clear. The high of has probably been reached. South wind around 5 mph.
Clear, with a low around . South wind around 5 mph. Patchy frost possible.
Sunny, with a high near . Light wind.
Mostly clear, with a low around . Northeast wind around 5 mph.
Sunny, with a high near . East wind around 5 mph.
Clear, with a low around . East wind around 5 mph.
Sunny, with a high near . East wind around 5 mph.
Clear, with a low around . Calm wind.
Mostly sunny, with a high near . Northeast wind around 5 mph.
Clear, with a low around . East wind around 5 mph.
Sunny, with a high near . Southeast wind around 5 mph.
Mostly clear, with a low around . Southeast wind around 5 mph.
Mostly sunny, with a high near . Southeast wind around 5 mph.
Partly cloudy, with a low around . South wind around 5 mph.
Highs, lows and rain chances are our forecast, the same numbers as the table below. The sky and wind words come from the four weather models' average, so they are only as good as the models' clouds. Wind is at the models' standard 33 feet; the station's sheltered sensor usually reads less. Why the forecast says this.
Next 7 days
| Daytime high 8 AM to 8 PM |
Overnight low that night, 8 PM to 9 AM |
Rain chance, day | Rain chance, night | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Day | Our forecast | NWS | WxSim | Our forecast | NWS | WxSim | Our forecast | NWS | Our forecast | NWS |
| Sun Oct 18 | ±1 so far 68° 8 AM forecast 63° |
63° | – | ±3 | 36° | 36° | 5% | 0% | 8% | 0% |
| Mon Oct 19 | ±3 | 68° | 68° | ±3 | 38° | 36° | 5% | 0% | 9% | 0% |
| Tue Oct 20 | ±3 | 69° | 69° | ±4 | 41° | 39° | 6% | 0% | 8% | 0% |
| Wed Oct 21 | ±3 | 70° | 71° | ±5 | 42° | 38° | 6% | 0% | 8% | 0% |
| Thu Oct 22 | ±4 | 71° | 70° | ±6 | 45° | 38° | 6% | 0% | 8% | 1% |
| Fri Oct 23 | ±6 | 67° | – | ±7 | 42° | – | 6% | 0% | 8% | 0% |
| Sat Oct 24 | ±7 | 68° | – | ±8 | 45° | – | 8% | 0% | 13% | 0% |
Once a high or low period has begun, its number is updated every hour with how warm or cool the station is running against the forecast, and it never goes below the high so far (or above the low so far) Tested. The forecast made before the period began is shown under it: that is the one the scoreboard grades. Tap any of our highs or lows (the dotted numbers) to see how we got it. The periods are fixed in universal time, the way the National Weather Service counts them, so they run an hour later during daylight saving time.
Rain chance means at least 0.01″ in this gauge during that 12-hour period; amounts show when the chance is 30% or more. NWS is the National Weather Service point forecast for this spot.
Highs and lows at a glance
Blue line: our forecast, with its 80% range shaded. Green squares: NWS. The table above has every number.
Forecast discussion run of Sun Oct 18, 6:45 PM
Watches and warningsA Frost Advisory is in effect until 9 AM Monday, from the National Weather Service office for Northern Indiana.
The official wording is in the banner at the top of this page.
SynopsisOver the next week, highs range from 68° on Monday to 71° on Wednesday. No period looks likely to be wet; the best chance is Saturday night, at 13%.
TemperaturesToday's high so far is 68°. Going by how the station is running, we now expect about 68°. Our 8 AM forecast was 63°, and that is the one we are graded on.
Tonight's low: we say 36°, 2° colder than the models' average (38°). The main reason: it should be a clear, calm night, and this spot cools faster than the models expect on those. A smaller push in the same direction: the time of year; the models usually run a little warm here this season.
Monday's high: we say 68°, 2° warmer than the models' average (66°). The main reason: it should be a sunny day, and the models tend to undersell how warm sunny days get here. A smaller push in the same direction: cloud or wind should keep the night from cooling as much as usual.
Monday's low: we say 38°, 2° colder than the models' average (40°). The main reason: it should be a clear, calm night, and this spot cools faster than the models expect on those. A smaller push in the same direction: the time of year; the models usually run a little warm here this season.
Tuesday's high: we say 70°, 3° warmer than the models' average (67°). The main reason: it should be a sunny day, and the models tend to undersell how warm sunny days get here. It's partly offset by the time of year; the models usually run a little warm here this season.
Tuesday's low: we say 40°, 2° colder than the models' average (42°). The main reason: it should be a clear, calm night, and this spot cools faster than the models expect on those. A smaller push in the same direction: the time of year; the models usually run a little warm here this season.
Wednesday's high: we say 71°, 5° warmer than the models' average (66°). The main reason: cloud or wind should keep the night from cooling as much as usual. It's partly offset by the time of year; the models usually run a little warm here this season.
Wednesday's low: we say 40°, 3° colder than the models' average (43°). The main reason: it should be a clear, calm night, and this spot cools faster than the models expect on those. A smaller push in the same direction: the time of year; the models usually run a little warm here this season.
Wednesday night looks like good radiational-cooling setup: a clear sky and light wind let the ground lose its heat straight to space. On nights like that, this spot usually gets colder than the models expect, which is why our lows run below theirs.
PrecipitationEvery 12-hour period looks mostly dry: fewer than 3 in 10 ensemble runs show measurable rain at any point.
HazardsTonight: a good chance of frost (58%). Low near 36°. Frost forms most readily when the sky clears and the wind goes calm.
Monday night: a small chance of frost (17%). Low near 38°.
Wednesday night: a small chance of frost (16%). Low near 40°.
Friday night: a small chance of frost (17%). Low near 41°.
ConfidenceThe ensemble is the same forecast run 122 times from slightly different starting points; the closer the runs agree, the more the forecast can be trusted. For the daytime highs, here is where 8 out of 10 runs land: today, very sure (60° to 62°); Monday, very sure (63° to 66°); Tuesday, very sure (65° to 67°); Wednesday, fairly sure (60° to 67°); Thursday, fairly sure (62° to 68°).
FrontsA front went through here around 1 AM Saturday: the dew point fell about 10° below normal, the wind swung from the northwest to the north, and the pressure rose 9.8 mb. On the latest national weather map, the nearest cold front is about 580 miles to the northwest, and Somerset is still ahead of it.
Changes since yesterdayThursday's high has moved up 5° since this time yesterday (from 66° to 70°). A forecast that keeps moving like this is still settling, so give it a little less trust than usual.
Written automatically from this run's numbers each hour: where our forecast differs from the models and the National Weather Service and why, hazards, fronts, and how the forecast has changed. It states what the data show and adds no judgment beyond them.
The next six hours, updated with what's happening now Tested
The station is reading 3.5° warmer than this forecast expected for now. The airports the wind is coming from are reading 5.3° warmer than the models expected, and that air is heading this way. Both differences tend to last a few hours, so the next six hours are corrected for them, less each hour.
Updated forecast = model forecast + delta from the station + delta from upwind (to the nearest tenth).
| Hour | Model forecast | Delta from the station | Delta from upwind | Updated forecast |
|---|---|---|---|---|
| 7 PM | 58.0° | +2.7° | +1.9° | 62.6° |
| 8 PM | 49.9° | +1.9° | +2.5° | 54.3° |
| 9 PM | 47.3° | +1.4° | +2.2° | 50.9° |
| 10 PM | 45.5° | +1.0° | +1.9° | 48.4° |
| 11 PM | 43.9° | +0.7° | +1.8° | 46.4° |
| 12 AM | 42.8° | +0.5° | +1.6° | 44.9° |
Model forecast: the four weather models' hour-by-hour temperature, adjusted by our tested correction for this station's highs and lows. Delta from the station: the station is reading a different temperature than the forecast expected right now, and that difference usually hangs on for a few hours. This column is the part of it carried into each hour, smaller each hour as it fades. Delta from upwind: the same thing for the airports the wind is blowing from, since their air arrives here over the next few hours. How much of each difference to carry forward, and how fast to fade it, was worked out from thousands of past hours. In a fair test on hours set aside for grading, the updated forecast's typical miss two hours ahead was about 1.5°, against 2.1° for the model forecast alone.
The next 48 hours, hour by hour
The shaded band is the range the ensembles allow (10th to 90th percentile, moved to our temperature). Gray bands are night. The dashed green line is the grass estimate, shown at night only. The thin line marks 32°.
Hour by hour, in detail
| Time | Weather rule | Temp ours | Likely range | Feels like | Dew point | Humidity | Wind models | Gust | Pressure | Clouds all / low-mid-high |
Rain chance / amt | Grass rule | WxSim | NWS | Lifted index index | K index | Total Totals | Freezing level level ft |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunday, Oct 18 | ||||||||||||||||||
| 6 PM | Sunny | 66.1° | 65-68 | 34.7° | 31% | S 7 | 12 | 30.40 | 0% 0-0-0 | 0% | 62.7° | 59° | +17.2 | -18 | 11 | 13,700 | ||
| ☾ Sunset 6:58 PM | ||||||||||||||||||
| 7 PM | Clear | 62.6° | 62-64 | 35.4° | 36% | S 6 | 10 | 30.41 | 0% 0-0-0 | 0% | 56.7° | 57.5° | 56° | +17.9 | -16 | 13 | 13,800 | |
| 8 PM | Clear | 54.3° | 53-56 | 35.6° | 49% | SSE 6 | 9 | 30.42 | 0% 0-0-0 | 0% | 48.3° | 52.7° | 52° | +19.4 | -15 | 15 | 13,800 | |
| 9 PM | Clear | 50.9° | 49-53 | 36.3° | 57% | SSE 5 | 8 | 30.42 | 0% 0-0-0 | 0% | 44.8° | 48.9° | 49° | +19.4 | -11 | 19 | 13,700 | |
| 10 PM | Clear | 48.4° | 46-51 | 46° | 36.7° | 64% | SSE 6 | 9 | 30.42 | 0% 0-0-0 | 0% | 42.4° | 46.5° | 46° | +20.6 | -9 | 21 | 13,600 |
| 11 PM | Clear | 46.4° | 44-49 | 44° | 35.7° | 66% | SSE 6 | 9 | 30.43 | 0% 0-0-0 | 0% | 40.3° | 44.7° | 44° | +21.9 | -8 | 22 | 13,800 |
| Monday, Oct 19 | ||||||||||||||||||
| 12 AM | Clear | 44.9° | 42-47 | 42° | 35.2° | 69% | SSE 6 | 10 | 30.43 | 0% 0-0-0 | 0% | 38.9° | 43.3° | 43° | +22.6 | -7 | 23 | 13,900 |
| 1 AM | Clear | 43.7° | 40-46 | 41° | 34.8° | 70% | SSE 5 | 10 | 30.42 | 0% 0-0-0 | 0% | 37.6° | 42.1° | 42° | +22.9 | -6 | 24 | 13,800 |
| 2 AM | Clear | 42.2° | 38-44 | 39° | 35.0° | 75% | SSE 6 | 10 | 30.41 | 0% 0-0-0 | 0% | 36.2° | 41.1° | 41° | +23.1 | -6 | 24 | 13,700 |
| 3 AM | Clear, dew | 40.9° | 37-43 | 37° | 34.9° | 79% | S 5 | 9 | 30.41 | 0% 0-0-0 | 0% | 34.6° | 40.2° | 40° | +23.2 | -6 | 24 | 13,100 |
| 4 AM | Clear, dew | 39.7° | 36-43 | 34.5° | 81% | S 5 | 8 | 30.42 | 0% 0-0-0 | 0% | 33.0° | 39.4° | 38° | +23.8 | -6 | 23 | 12,700 | |
| 5 AM | Clear, dew | 38.8° | 35-42 | 34.1° | 83% | S 4 | 7 | 30.42 | 0% 0-0-0 | 0% | 32.6° | 38.7° | 37° | +24.3 | -7 | 22 | 12,600 | |
| 6 AM | Clear, dew | 37.8° | 34-41 | 33.8° | 85% | S 4 | 7 | 30.43 | 0% 0-0-0 | 0% | 32.3° | 38.1° | 37° | +24.7 | -8 | 21 | 12,100 | |
| 7 AM | Clear, dew | 36.6° | 33-40 | 33.5° | 89% | S 4 | 6 | 30.43 | 1% 0-0-0 | 0% | 32.0° | 37.6° | 36° | +25.2 | -10 | 20 | 12,300 | |
| ☀︎ Sunrise 7:59 AM | ||||||||||||||||||
| 8 AM | Clear, dew | 38.3° | 33-41 | 33.5° | 83% | SSE 3 | 5 | 30.44 | 1% 1-0-0 | 0% | 32.0° | 36.5° | 36° | +25.7 | -10 | 19 | 12,300 | |
| 9 AM | Sunny | 42.8° | 35-45 | 34.9° | 73% | SSE 3 | 5 | 30.45 | 1% 1-0-0 | 0% | 38.0° | 40° | +25.6 | -12 | 19 | 12,600 | ||
| 10 AM | Sunny | 50.2° | 45-52 | 37.1° | 61% | S 3 | 5 | 30.45 | 0% 0-0-0 | 0% | 43.3° | 48° | +21.6 | -14 | 19 | 13,000 | ||
| 11 AM | Sunny | 56.5° | 55-57 | 39.0° | 52% | SSW 2 | 5 | 30.45 | 0% 0-0-0 | 0% | 50.4° | 55° | +18.0 | -15 | 19 | 13,100 | ||
| 12 PM | Sunny | 61.0° | 60-62 | 40.3° | 46% | S 2 | 4 | 30.44 | 0% 0-0-0 | 0% | 56.6° | 59° | +16.5 | -13 | 20 | 13,000 | ||
| 1 PM | Sunny | 64.4° | 64-66 | 40.3° | 41% | S 2 | 5 | 30.41 | 0% 0-0-0 | 0% | 61.3° | 62° | +15.6 | -13 | 21 | 12,700 | ||
| 2 PM | Sunny | 66.4° | 65-68 | 39.9° | 38% | SSE 2 | 6 | 30.38 | 0% 0-0-0 | 0% | 64.8° | 65° | +15.0 | -12 | 22 | 12,400 | ||
| 3 PM | Sunny | 67.5° | 67-69 | 39.7° | 36% | SSE 2 | 6 | 30.36 | 0% 0-0-0 | 0% | 66.3° | 66° | +14.4 | -12 | 23 | 12,100 | ||
| 4 PM | Sunny | 68.1° | 67-70 | 39.4° | 35% | SSE 2 | 6 | 30.35 | 0% 0-0-0 | 0% | 66.9° | 66° | +14.3 | -12 | 23 | 12,100 | ||
| 5 PM | Sunny | 67.8° | 67-69 | 39.6° | 36% | SE 1 | 5 | 30.34 | 0% 0-0-0 | 0% | 66.0° | 67° | +14.1 | -11 | 23 | 12,100 | ||
| 6 PM | Sunny | 66.3° | 66-68 | 40.5° | 39% | ENE 1 | 3 | 30.34 | 0% 0-0-4 | 0% | 62.7° | 64° | +14.2 | -10 | 23 | 12,000 | ||
| ☾ Sunset 6:57 PM | ||||||||||||||||||
| 7 PM | Clear | 61.7° | 61-63 | 39.8° | 44% | NNE 3 | 4 | 30.34 | 1% 0-0-10 | 0% | 53.2° | 57.1° | 61° | +15.0 | -9 | 24 | 11,800 | |
| 8 PM | Clear | 53.8° | 53-55 | 41.4° | 63% | NNE 4 | 6 | 30.35 | 2% 0-0-16 | 0% | 46.4° | 51.9° | 58° | +14.9 | -8 | 24 | 11,600 | |
| 9 PM | Clear | 51.0° | 50-53 | 41.1° | 69% | NE 4 | 6 | 30.36 | 3% 0-0-20 | 0% | 44.1° | 47.9° | 52° | +15.5 | -9 | 23 | 11,600 | |
| 10 PM | Clear, dew | 48.5° | 47-51 | 41.0° | 75% | NE 4 | 6 | 30.36 | 4% 0-0-23 | 0% | 41.8° | 45.4° | 50° | +16.0 | -8 | 24 | 11,400 | |
| 11 PM | Mostly clear, dew | 46.4° | 44-50 | 41.1° | 82% | ENE 4 | 6 | 30.36 | 30% 0-0-48 | 0% | 41.3° | 43.6° | 48° | +16.4 | -8 | 24 | 11,600 | |
| Tuesday, Oct 20 | ||||||||||||||||||
| 12 AM | Mostly clear, dew | 45.1° | 42-49 | 40.7° | 84% | ENE 4 | 6 | 30.37 | 39% 0-0-52 | 0% | 40.4° | 42.2° | 46° | +16.3 | -8 | 24 | 11,700 | |
| 1 AM | Partly cloudy, dew | 44.0° | 41-49 | 40.2° | 86% | ENE 4 | 6 | 30.36 | 46% 0-0-53 | 0% | 40.0° | 41.0° | 45° | +16.5 | -9 | 24 | 11,700 | |
| 2 AM | Partly cloudy, dew | 42.9° | 39-48 | 39.9° | 89% | ENE 4 | 5 | 30.36 | 56% 2-0-59 | 0% | 39.5° | 40.1° | 45° | +16.8 | -9 | 25 | 11,800 | |
| 3 AM | Partly cloudy, dew | 42.0° | 38-47 | 39.4° | 90% | ENE 4 | 5 | 30.36 | 56% 4-0-46 | 0% | 38.6° | 39.2° | 43° | +17.2 | -9 | 25 | 11,800 | |
| 4 AM | Partly cloudy, dew | 41.1° | 37-46 | 38.7° | 91% | E 4 | 5 | 30.37 | 54% 6-0-44 | 0% | 37.5° | 38.5° | 42° | +18.1 | -9 | 24 | 11,600 | |
| 5 AM | Partly cloudy, dew | 40.3° | 36-45 | 38.4° | 93% | ENE 4 | 5 | 30.37 | 46% 7-0-45 | 0% | 36.9° | 38.0° | 41° | +19.0 | -9 | 24 | 11,500 | |
| 6 AM | Mostly clear, dew | 39.4° | 35-44 | 37.9° | 94% | ENE 3 | 5 | 30.38 | 33% 10-0-32 | 0% | 36.4° | 37.5° | 40° | +19.5 | -9 | 24 | 11,500 | |
| 7 AM | Mostly clear, dew | 38.6° | 35-44 | 37.2° | 95% | ENE 4 | 5 | 30.39 | 28% 12-0-28 | 0% | 35.7° | 37.0° | 38° | +19.9 | -9 | 23 | 11,300 | |
| 8 AM | Clear, dew | 40.5° | 36-45 | 37.2° | 88% | ENE 4 | 6 | 30.40 | 13% 16-0-14 | 0% | 35.7° | 36.6° | 38° | +20.4 | -10 | 23 | 11,300 | |
| ☀︎ Sunrise 8:00 AM | ||||||||||||||||||
| 9 AM | Sunny | 44.9° | 41-49 | 39.3° | 81% | ENE 4 | 6 | 30.41 | 4% 17-0-5 | 0% | 38.5° | 42° | +20.5 | -10 | 22 | 11,100 | ||
| 10 AM | Sunny | 52.0° | 48-54 | 42.3° | 69% | E 4 | 7 | 30.41 | 2% 0-0-4 | 0% | 44.0° | 49° | +17.5 | -10 | 22 | 11,100 | ||
| 11 AM | Sunny | 58.0° | 55-60 | 43.5° | 58% | E 4 | 8 | 30.41 | 14% 0-0-16 | 0% | 51.5° | 56° | +14.9 | -10 | 22 | 11,000 | ||
| 12 PM | Sunny | 63.2° | 61-65 | 43.6° | 49% | E 4 | 9 | 30.40 | 6% 0-0-8 | 0% | 57.9° | 61° | +13.3 | -10 | 23 | 11,000 | ||
| 1 PM | Sunny | 66.4° | 65-68 | 42.7° | 42% | E 4 | 9 | 30.38 | 4% 0-1-4 | 0% | 62.6° | 64° | +12.4 | -10 | 23 | 11,100 | ||
| 2 PM | Sunny | 68.2° | 67-69 | 41.6° | 38% | E 4 | 8 | 30.36 | 4% 0-2-2 | 0% | 66.2° | 66° | +12.4 | -10 | 24 | 11,200 | ||
| 3 PM | Sunny | 69.3° | 68-70 | 41.0° | 36% | E 4 | 8 | 30.34 | 4% 0-1-2 | 0% | 67.8° | 68° | +11.6 | -10 | 24 | 11,400 | ||
| 4 PM | Sunny | 69.7° | 69-71 | 41.1° | 35% | ENE 4 | 7 | 30.32 | 4% 0-1-1 | 0% | 68.2° | 69° | +11.6 | -11 | 23 | 11,400 | ||
| 5 PM | Sunny | 69.3° | 68-71 | 41.2° | 36% | ENE 4 | 7 | 30.32 | 4% 0-1-2 | 0% | 67.3° | 68° | +11.3 | -11 | 23 | 11,200 | ||
| 6 PM | Sunny | 67.0° | 66-68 | 42.5° | 41% | ENE 5 | 7 | 30.32 | 4% 0-1-4 | 0% | 64.0° | 66° | +10.8 | -11 | 23 | 11,200 | ||
| ☾ Sunset 6:55 PM | ||||||||||||||||||
Times are local. Shaded rows are night. Wind and gusts in mph at 10 m, pressure in inches at sea level, rain chance is the share of ensemble runs with rain that hour, amount is the models' average. Scroll sideways on a phone; the time stays put.
How to read it
Temp ours. Our daily high and low corrections are tested against the station; the hour-to-hour shape between them comes from the models. A correction of that shape was tested and narrowly missed its bar, so the shape is the models' own.
Range. 10th to 90th percentile of about 120 ensemble runs, moved to sit around our temperature.
Feels. Wind chill at 50° or colder with wind of 5 mph or more; heat index at 80° or warmer. Shown only when it differs by a degree or more.
Grass rule. Night only. On a clear, calm night the grass runs up to 12° below the air, less with cloud and wind; once dew forms it is held about 1.5° below the dew point. Starting values come from the ground sensor's first night (October 17, 2026) and will be refit as nights add up. See the Ground page for the real readings.
Weather rule. Sky from cloud cover; precipitation when the models or at least half the ensemble runs bring it, snow when the wet-bulb temperature is 32.5° or lower (falling snow cools dry air as it evaporates, so it can snow at 35°), otherwise rain; frost when the grass estimate reaches 32° at the dew point (light 30-32°, frost 27-30°, heavy below 27°), dew above 32°; fog when visibility drops under a mile or the air is saturated and nearly calm.
Stability. Lifted index (GFS): below 0 the air is unstable, below -4 strongly so. K index: above 30, thunderstorms are likely. Total Totals: above 50, storms possible. All three come from the models' temperatures and moisture at 850, 700 and 500 mb (about 5,000, 10,000 and 18,000 ft).
WxSim and NWS. Their own hourly temperatures, for comparison. WxSim is a commercial forecast program run on the station's computer; NWS is the National Weather Service office in Northern Indiana.
Calendar-day high and low midnight to midnight
| Day | High | Low |
|---|---|---|
| Sun Oct 18 | so far 69° Midnight forecast 63° | so far 32° Midnight forecast 33° |
| Mon Oct 19 | ±3 | ±3 |
| Tue Oct 20 | ±2 | ±3 |
| Wed Oct 21 | ±3 | ±4 |
| Thu Oct 22 | ±4 | ±6 |
| Fri Oct 23 | ±6 | ±7 |
| Sat Oct 24 | ±7 | ±8 |
The same day measured the way the station's records and the NOAA monthly report count it. On days a front comes through, the high can land just after midnight, so these can differ from the daytime high and overnight low above.
Go deeper
- How accurate it is: the live scoreboard against the National Weather Service and WxSim, the fair test on a year set aside for grading, and the miss review.
- Every number behind this run: each weather model's guidance, where our forecast sits in the 122-run ensemble, rain by 12-hour period, and how the forecast has moved from run to run.
- Model charts: the week ahead hour by hour from the models, at the ground and in the air above.
- Lab Notebook: every change to the forecast is tested there first, in the open, including the ones that failed.
Sunday, Oct 18, daytime high
How we got 68°:
| Models' average (the blend) | 62.7° | start |
| Station baseline | +1.3° | |
| Forecast sunshine | +0.9° | |
| Expected cloud cover | +0.4° | |
| Season | −0.3° | |
| Dryness (dew-point depression) | −0.2° | |
| Clear & calm (radiational cooling) | +0.1° | |
| Instability (CAPE) | −0.1° | |
| How warm or cold the blend runs | +0.0° | |
| Expected wind | +0.0° | |
| Model disagreement | +0.0° | |
| Models' recent error here | +0.0° | |
| Our forecast | 64.8° | = blend +2.1°, shown as 65° |
| Updated with the station | 68° | high so far 68° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
| 3 days ago | 2 days ago | a day ago | latest run | |
| Ours | 64° | 64° | 63° | 65° |
| NWS | 64° | 62° | 63° | 63° |
Our forecast as each run issued it, before any update from the station.
Sunday, Oct 18, overnight low
How we got 36°:
| Models' average (the blend) | 37.7° | start |
| Clear & calm (radiational cooling) | −1.6° | |
| Station baseline | −0.6° | |
| Season | −0.5° | |
| Expected cloud cover | +0.4° | |
| Expected wind | +0.1° | |
| How warm or cold the blend runs | +0.1° | |
| Dryness (dew-point depression) | +0.1° | |
| Model disagreement | +0.0° | |
| Models' recent error here | +0.0° | |
| Our forecast | 35.6° | = blend −2.1°, shown as 36° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
| 3 days ago | 2 days ago | a day ago | latest run | |
| Ours | 37° | 36° | 35° | 36° |
| NWS | 37° | 35° | 35° | 36° |
Our forecast as each run issued it, before any update from the station.
Monday, Oct 19, daytime high
How we got 68°:
| Models' average (the blend) | 65.6° | start |
| Station baseline | +1.5° | |
| Forecast sunshine | +1.3° | |
| Clear & calm (radiational cooling) | +0.8° | |
| Season | −0.7° | |
| Dryness (dew-point depression) | −0.3° | |
| Instability (CAPE) | +0.2° | |
| Expected wind | −0.1° | |
| Expected cloud cover | −0.1° | |
| Model disagreement | −0.1° | |
| How warm or cold the blend runs | +0.0° | |
| Models' recent error here | +0.0° | |
| Our forecast | 68.1° | = blend +2.5°, shown as 68° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
| 3 days ago | 2 days ago | a day ago | latest run | |
| Ours | 69° | 68° | 68° | 68° |
| NWS | 69° | 68° | 67° | 68° |
Our forecast as each run issued it, before any update from the station.
Monday, Oct 19, overnight low
How we got 38°:
| Models' average (the blend) | 39.7° | start |
| Clear & calm (radiational cooling) | −1.0° | |
| Season | −0.6° | |
| Station baseline | −0.5° | |
| How warm or cold the blend runs | +0.5° | |
| Dryness (dew-point depression) | +0.4° | |
| Model disagreement | −0.1° | |
| Expected cloud cover | −0.1° | |
| Models' recent error here | +0.0° | |
| Expected wind | +0.0° | |
| Our forecast | 38.2° | = blend −1.5°, shown as 38° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
| 3 days ago | 2 days ago | a day ago | latest run | |
| Ours | 43° | 37° | 38° | 38° |
| NWS | 41° | 37° | 37° | 38° |
Our forecast as each run issued it, before any update from the station.
Tuesday, Oct 20, daytime high
How we got 70°:
| Models' average (the blend) | 66.9° | start |
| Station baseline | +1.5° | |
| Forecast sunshine | +0.8° | |
| Season | −0.7° | |
| Instability (CAPE) | +0.7° | |
| Expected cloud cover | +0.5° | |
| Clear & calm (radiational cooling) | +0.5° | |
| Dryness (dew-point depression) | −0.5° | |
| Model disagreement | −0.1° | |
| How warm or cold the blend runs | +0.1° | |
| Expected wind | +0.0° | |
| Models' recent error here | +0.0° | |
| Our forecast | 69.7° | = blend +2.8°, shown as 70° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
| 3 days ago | 2 days ago | a day ago | latest run | |
| Ours | 70° | 69° | 70° | 70° |
| NWS | 71° | 70° | 71° | 69° |
Our forecast as each run issued it, before any update from the station.
Tuesday, Oct 20, overnight low
How we got 40°:
| Models' average (the blend) | 41.6° | start |
| Clear & calm (radiational cooling) | −1.3° | |
| Station baseline | −0.6° | |
| Season | −0.6° | |
| Dryness (dew-point depression) | +0.4° | |
| How warm or cold the blend runs | +0.4° | |
| Expected cloud cover | −0.1° | |
| Expected wind | +0.1° | |
| Model disagreement | +0.0° | |
| Models' recent error here | +0.0° | |
| Our forecast | 40.0° | = blend −1.6°, shown as 40° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
| 3 days ago | 2 days ago | a day ago | latest run | |
| Ours | 43° | 39° | 40° | 40° |
| NWS | 42° | 41° | 40° | 41° |
Our forecast as each run issued it, before any update from the station.
Wednesday, Oct 21, daytime high
How we got 71°:
| Models' average (the blend) | 66.3° | start |
| Clear & calm (radiational cooling) | +1.8° | |
| Season | −1.6° | |
| Instability (CAPE) | +1.5° | |
| Forecast sunshine | +1.5° | |
| Station baseline | +1.5° | |
| Model disagreement | +0.6° | |
| Dryness (dew-point depression) | −0.5° | |
| Expected cloud cover | +0.3° | |
| How warm or cold the blend runs | +0.1° | |
| Expected wind | −0.1° | |
| Models' recent error here | +0.0° | |
| Our forecast | 71.2° | = blend +4.9°, shown as 71° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
| 3 days ago | 2 days ago | a day ago | latest run | |
| Ours | 69° | 70° | 70° | 71° |
| NWS | 72° | 71° | 71° | 70° |
Our forecast as each run issued it, before any update from the station.
Wednesday, Oct 21, overnight low
How we got 40°:
| Models' average (the blend) | 42.6° | start |
| Clear & calm (radiational cooling) | −2.5° | |
| Season | −0.7° | |
| Station baseline | −0.5° | |
| Dryness (dew-point depression) | +0.5° | |
| How warm or cold the blend runs | +0.3° | |
| Expected wind | +0.3° | |
| Expected cloud cover | −0.1° | |
| Models' recent error here | +0.1° | |
| Model disagreement | +0.0° | |
| Our forecast | 39.9° | = blend −2.7°, shown as 40° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
| 3 days ago | 2 days ago | a day ago | latest run | |
| Ours | 42° | 41° | 40° | 40° |
| NWS | 44° | 42° | 43° | 42° |
Our forecast as each run issued it, before any update from the station.
Thursday, Oct 22, daytime high
How we got 70°:
| Models' average (the blend) | 66.8° | start |
| Season | −1.7° | |
| Clear & calm (radiational cooling) | +1.6° | |
| Station baseline | +1.6° | |
| Forecast sunshine | +1.5° | |
| Instability (CAPE) | +1.3° | |
| Expected cloud cover | −0.5° | |
| Model disagreement | +0.3° | |
| Dryness (dew-point depression) | −0.3° | |
| Expected wind | −0.2° | |
| How warm or cold the blend runs | +0.0° | |
| Models' recent error here | +0.0° | |
| Our forecast | 70.4° | = blend +3.6°, shown as 70° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
| 2 days ago | a day ago | latest run | |
| Ours | 68° | 66° | 70° |
| NWS | 73° | 73° | 71° |
Our forecast as each run issued it, before any update from the station.
Thursday, Oct 22, overnight low
How we got 43°:
| Models' average (the blend) | 44.6° | start |
| Clear & calm (radiational cooling) | −1.2° | |
| Season | −1.1° | |
| Model disagreement | +0.4° | |
| Expected cloud cover | −0.4° | |
| Dryness (dew-point depression) | +0.3° | |
| Station baseline | −0.2° | |
| Expected wind | +0.2° | |
| How warm or cold the blend runs | +0.2° | |
| Models' recent error here | +0.1° | |
| Our forecast | 43.0° | = blend −1.6°, shown as 43° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
| 2 days ago | a day ago | latest run | |
| Ours | 46° | 45° | 43° |
| NWS | 45° | 45° | 45° |
Our forecast as each run issued it, before any update from the station.
Friday, Oct 23, daytime high
How we got 69°:
| Models' average (the blend) | 66.0° | start |
| Forecast sunshine | +2.1° | |
| Station baseline | +1.8° | |
| Season | −1.7° | |
| Clear & calm (radiational cooling) | +0.8° | |
| Expected cloud cover | −0.8° | |
| Instability (CAPE) | +0.7° | |
| Dryness (dew-point depression) | −0.2° | |
| Expected wind | −0.2° | |
| Model disagreement | +0.1° | |
| How warm or cold the blend runs | +0.0° | |
| Models' recent error here | +0.0° | |
| Our forecast | 68.5° | = blend +2.5°, shown as 69° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Friday, Oct 23, overnight low
How we got 41°:
| Models' average (the blend) | 41.2° | start |
| Season | −1.3° | |
| Model disagreement | +0.8° | |
| How warm or cold the blend runs | +0.5° | |
| Expected cloud cover | −0.3° | |
| Dryness (dew-point depression) | +0.3° | |
| Station baseline | +0.2° | |
| Models' recent error here | +0.1° | |
| Clear & calm (radiational cooling) | −0.1° | |
| Expected wind | −0.1° | |
| Our forecast | 41.3° | = blend +0.1°, shown as 41° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Saturday, Oct 24, daytime high
How we got 68°:
| Models' average (the blend) | 67.2° | start |
| Season | −2.3° | |
| Forecast sunshine | +2.0° | |
| Station baseline | +1.4° | |
| Instability (CAPE) | +0.8° | |
| Dryness (dew-point depression) | −0.7° | |
| Expected cloud cover | −0.3° | |
| Clear & calm (radiational cooling) | +0.3° | |
| Expected wind | −0.1° | |
| How warm or cold the blend runs | −0.1° | |
| Model disagreement | +0.0° | |
| Models' recent error here | +0.0° | |
| Our forecast | 68.3° | = blend +1.1°, shown as 68° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Saturday, Oct 24, overnight low
How we got 46°:
| Models' average (the blend) | 47.1° | start |
| Season | −1.7° | |
| Station baseline | +0.8° | |
| How warm or cold the blend runs | −0.1° | |
| Model disagreement | +0.0° | |
| Models' recent error here | +0.0° | |
| Expected wind | +0.0° | |
| Expected cloud cover | +0.0° | |
| Dryness (dew-point depression) | +0.0° | |
| Clear & calm (radiational cooling) | +0.0° | |
| Our forecast | 46.1° | = blend −1.0°, shown as 46° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Sunday, Oct 18, high for the calendar day
How we got 69°:
| Models' average (the blend) | 62.7° | start |
| Station baseline | +1.4° | |
| Forecast sunshine | +0.8° | |
| Expected cloud cover | +0.5° | |
| Models' recent error here | +0.3° | |
| Season | −0.3° | |
| Clear & calm (radiational cooling) | +0.2° | |
| Dryness (dew-point depression) | −0.2° | |
| Instability (CAPE) | −0.1° | |
| Expected wind | −0.1° | |
| How warm or cold the blend runs | +0.0° | |
| Model disagreement | +0.0° | |
| Our forecast | 65.1° | = blend +2.4°, shown as 65° |
| Updated with the station | 69° | high so far 69° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Sunday, Oct 18, low for the calendar day
How we got 32°:
| Models' average (the blend) | 33.7° | start |
| Station baseline | −0.8° | |
| Season | −0.6° | |
| Clear & calm (radiational cooling) | −0.5° | |
| Models' recent error here | −0.1° | |
| Dryness (dew-point depression) | +0.1° | |
| How warm or cold the blend runs | −0.1° | |
| Model disagreement | +0.1° | |
| Expected cloud cover | +0.1° | |
| Expected wind | +0.0° | |
| Our forecast | 31.9° | = blend −1.8°, shown as 32° |
| Updated with the station | 32° | low so far 32° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Monday, Oct 19, high for the calendar day
How we got 68°:
| Models' average (the blend) | 65.6° | start |
| Station baseline | +1.5° | |
| Forecast sunshine | +1.1° | |
| Clear & calm (radiational cooling) | +0.9° | |
| Season | −0.7° | |
| Dryness (dew-point depression) | −0.5° | |
| Instability (CAPE) | +0.3° | |
| Models' recent error here | +0.2° | |
| Expected wind | −0.2° | |
| Expected cloud cover | +0.1° | |
| Model disagreement | +0.0° | |
| How warm or cold the blend runs | +0.0° | |
| Our forecast | 68.2° | = blend +2.6°, shown as 68° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Monday, Oct 19, low for the calendar day
How we got 37°:
| Models' average (the blend) | 37.7° | start |
| Season | −0.8° | |
| Station baseline | −0.7° | |
| How warm or cold the blend runs | +0.5° | |
| Clear & calm (radiational cooling) | −0.4° | |
| Expected wind | +0.3° | |
| Dryness (dew-point depression) | +0.2° | |
| Models' recent error here | +0.1° | |
| Model disagreement | +0.1° | |
| Expected cloud cover | +0.0° | |
| Our forecast | 37.0° | = blend −0.7°, shown as 37° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Tuesday, Oct 20, high for the calendar day
How we got 70°:
| Models' average (the blend) | 66.9° | start |
| Station baseline | +1.5° | |
| Expected cloud cover | +0.9° | |
| Season | −0.8° | |
| Dryness (dew-point depression) | −0.8° | |
| Instability (CAPE) | +0.8° | |
| Forecast sunshine | +0.8° | |
| Models' recent error here | +0.3° | |
| Clear & calm (radiational cooling) | +0.3° | |
| Model disagreement | −0.1° | |
| How warm or cold the blend runs | +0.0° | |
| Expected wind | +0.0° | |
| Our forecast | 69.8° | = blend +2.9°, shown as 70° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Tuesday, Oct 20, low for the calendar day
How we got 39°:
| Models' average (the blend) | 39.7° | start |
| Station baseline | −0.8° | |
| Season | −0.7° | |
| Clear & calm (radiational cooling) | −0.4° | |
| How warm or cold the blend runs | +0.3° | |
| Expected wind | +0.3° | |
| Dryness (dew-point depression) | +0.2° | |
| Models' recent error here | +0.2° | |
| Expected cloud cover | −0.1° | |
| Model disagreement | +0.0° | |
| Our forecast | 38.7° | = blend −1.0°, shown as 39° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Wednesday, Oct 21, high for the calendar day
How we got 72°:
| Models' average (the blend) | 66.3° | start |
| Clear & calm (radiational cooling) | +2.0° | |
| Season | −1.7° | |
| Instability (CAPE) | +1.4° | |
| Forecast sunshine | +1.4° | |
| Station baseline | +1.4° | |
| Dryness (dew-point depression) | −0.6° | |
| Model disagreement | +0.6° | |
| Expected cloud cover | +0.5° | |
| Models' recent error here | +0.4° | |
| Expected wind | −0.3° | |
| How warm or cold the blend runs | +0.0° | |
| Our forecast | 71.6° | = blend +5.3°, shown as 72° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Wednesday, Oct 21, low for the calendar day
How we got 40°:
| Models' average (the blend) | 41.6° | start |
| Clear & calm (radiational cooling) | −1.4° | |
| Season | −0.9° | |
| Station baseline | −0.7° | |
| Models' recent error here | +0.3° | |
| Expected wind | +0.3° | |
| How warm or cold the blend runs | +0.3° | |
| Dryness (dew-point depression) | +0.2° | |
| Expected cloud cover | +0.1° | |
| Model disagreement | +0.0° | |
| Our forecast | 39.8° | = blend −1.8°, shown as 40° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Thursday, Oct 22, high for the calendar day
How we got 71°:
| Models' average (the blend) | 66.8° | start |
| Clear & calm (radiational cooling) | +2.1° | |
| Season | −1.6° | |
| Station baseline | +1.4° | |
| Forecast sunshine | +1.4° | |
| Instability (CAPE) | +1.2° | |
| Expected cloud cover | −0.7° | |
| Expected wind | −0.6° | |
| Models' recent error here | +0.5° | |
| Model disagreement | +0.4° | |
| Dryness (dew-point depression) | −0.2° | |
| How warm or cold the blend runs | +0.0° | |
| Our forecast | 70.6° | = blend +3.8°, shown as 71° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Thursday, Oct 22, low for the calendar day
How we got 41°:
| Models' average (the blend) | 42.6° | start |
| Season | −1.1° | |
| Clear & calm (radiational cooling) | −0.9° | |
| Station baseline | −0.4° | |
| Models' recent error here | +0.4° | |
| Dryness (dew-point depression) | +0.3° | |
| Expected cloud cover | −0.3° | |
| How warm or cold the blend runs | +0.3° | |
| Model disagreement | +0.2° | |
| Expected wind | +0.1° | |
| Our forecast | 41.1° | = blend −1.5°, shown as 41° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Friday, Oct 23, high for the calendar day
How we got 69°:
| Models' average (the blend) | 66.0° | start |
| Season | −1.5° | |
| Forecast sunshine | +1.5° | |
| Station baseline | +1.5° | |
| Clear & calm (radiational cooling) | +0.7° | |
| Instability (CAPE) | +0.7° | |
| Models' recent error here | +0.5° | |
| Dryness (dew-point depression) | −0.3° | |
| Expected wind | −0.2° | |
| How warm or cold the blend runs | −0.1° | |
| Expected cloud cover | −0.1° | |
| Model disagreement | +0.0° | |
| Our forecast | 68.7° | = blend +2.7°, shown as 69° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Friday, Oct 23, low for the calendar day
How we got 44°:
| Models' average (the blend) | 44.6° | start |
| Season | −1.1° | |
| Model disagreement | +0.5° | |
| Clear & calm (radiational cooling) | −0.4° | |
| Models' recent error here | +0.3° | |
| Expected cloud cover | +0.3° | |
| Dryness (dew-point depression) | −0.2° | |
| Expected wind | −0.1° | |
| How warm or cold the blend runs | +0.1° | |
| Station baseline | +0.0° | |
| Our forecast | 43.9° | = blend −0.7°, shown as 44° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Saturday, Oct 24, high for the calendar day
How we got 68°:
| Models' average (the blend) | 67.2° | start |
| Season | −2.4° | |
| Forecast sunshine | +1.8° | |
| Station baseline | +1.1° | |
| Models' recent error here | +0.6° | |
| Dryness (dew-point depression) | −0.5° | |
| Instability (CAPE) | +0.5° | |
| Clear & calm (radiational cooling) | +0.5° | |
| Expected cloud cover | −0.3° | |
| Expected wind | −0.2° | |
| How warm or cold the blend runs | −0.1° | |
| Model disagreement | +0.0° | |
| Our forecast | 68.2° | = blend +1.0°, shown as 68° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.
Saturday, Oct 24, low for the calendar day
How we got 43°:
| Models' average (the blend) | 42.6° | start |
| Season | −1.6° | |
| Dryness (dew-point depression) | +0.9° | |
| Station baseline | +0.6° | |
| Models' recent error here | +0.2° | |
| How warm or cold the blend runs | +0.2° | |
| Model disagreement | +0.2° | |
| Expected cloud cover | −0.1° | |
| Clear & calm (radiational cooling) | +0.1° | |
| Expected wind | +0.0° | |
| Our forecast | 43.1° | = blend +0.5°, shown as 43° |
Start with the models' average, add each row (blue pushed it warmer, orange cooler), and you arrive at our forecast. Each row compares this period with an ordinary one: a factor that is typical adds nothing. The rows are rounded, so adding them by hand can be off by a tenth.