Monday Night: Partly Cloudy. Low: 55°F

Tuesday: Sunny. High: 82°F

Tuesday Night: Clear. Low: 56°F

Wednesday: Sunny. High: 73°F

Wednesday Night: Clear. Low: 47°F

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General Discussion:

Warm dry temperatures continue until Tuesday evening when a cold front and changing upper level wind directions will result in a cooling trend for the rest of the week though low relative humidity and increasing winds still make fire weather a significant risk.

– Aldrich, Bean, Carrier

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Forecasters: Aldrich, Bean, Carrier

Date Issued: 10/21/2024 9:00 AM CDT

Technical Discussion:

Key Messages

-Low RH values and increasing surface winds will produce an elevated risk of fire weather.

-A slight chance of light precipitation Tuesday morning.

-A northerly wind shift will push for cooler temperatures Wednesday.

The upper levels of the atmosphere for the beginning of this week are seeing a decent amount of activity starting with the weak trough currently centered over Colorado. This trough will move to the east northeast before deamplifying out of existence over the Great Lakes region on Tuesday night. Following this small trough a more significant trough will push down from Canada through Wednesday, just clipping northern Missouri and bringing with it a noteworthy jetstreak. After these two systems move through we will see a return to zonal flow with a northerly component of the wind following the cold front that is predicted to move through after the weak low moves out of the area. This will lend itself to the overall cooling trend for the latter half of the week.

We can expect cloud cover to be increasing overnight as moisture in the upper levels of the atmosphere increases though we should not expect much if any precipitation as we have a dry layer between around 700-750mb to the surface. A thin band of relative humidity values greater than 75% can be seen moving through the area in the mid morning on Tuesday, and while the models agree that this will be present at the 750mb level there is disagreement on if those higher moisture values will extend any lower in the atmosphere. This leaves the chances of rain overnight uncertain but unlikely and if any were to fall it should be expected in the early morning.

The shifting low pressure systems are expected to bring a cold front through the area though there is some disagreement in the models for what the conditions will be like once the front passes. As a result our confidence in temperatures past the Tuesday night timeframe is significantly lower and future forecast shifts should correct for this once a more uniform consensus is reached. The shifting low pressure systems will also cause an increase in surface winds as the pressure gradient force intensifies which along with the persistent drought conditions and low surface relative humidity poses the threat of returning fire weather. While no official warning of elevated fire weather risk has been made yet, individuals should still take enhanced care to control any intentionally made fires and prevent any unintentional fires from sparking.

-Aldrich, Bean, Carrier