Monday, September 30th – Afternoon Forecast

Monday Night: Clear Low: 60°F

Tuesday: Sunny High: 71°F

Tuesday Night: Clear Low: 40°F

Wednesday: Sunny High: 72°F

Wednesday Night: Clear Low: 50°F

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General Discussion:

After a very cloudy and windy weekend resulting from remnants of what was once Hurricane Helene, sunshine and average to slightly above average temperatures (75°F) have returned for the beginning of the work week, with highs having peaked in the low to mid 80s for much of the region. However, a dry cold front will sneak through the area early Tuesday morning, bringing relative humidity and dew point values down into the mid to upper 30s. Temperatures for the remainder of the work week will stay in the low to mid 70s. 

– Bean, Carrier, Aldrich

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Forecasters: Bean, Carrier, Aldrich

Date Issued: 09/30/2024 5:00 PM CDT

Technical Discussion:

Key Messages

• A dry cold front will arrive early Tuesday morning, providing windy conditions along with much lower humidity. 
• Calm, dry weather will continue throughout the rest of the work week with moderating temperatures. 

Looking at 250/300mb, there is currently a weak upper-level ridge situated over the Ohio River Valley and will continue to drift off to the east over the next 24 hours. The polar jet stream is in a meridional flow and will take a more zonal flow as an upper-level high pressure moves into the area starting 12z Wednesday. Looking at the 500mb level, once the dry cold front moves into the region Tuesday morning, sinking air associated with the high-pressure ridge, will provide for a sunny day and slightly cooler temperatures (upper 60s/low 70s).  

Moving down to 700mb, mid-low-level moisture continues to recede into Monday night and the rest of the forecast period. This is due to the remnant low pressure of Helene continuing to push off to the east, dragging all the moisture away from the area. At 850mb, a ridge of high-pressure will eject from the Rockies early Tuesday and will center itself in northwest Texas beginning 21z Tuesday. This high-pressure system will keep any moisture well south of the forecast area, resulting in several days of a mostly clear sky with abundant sunshine. 

A mostly clear sky with abundant sunshine will persist through the first part of the work week as temperatures will make their way into the low to mid 70s. Breezy conditions will follow the cold front’s arrival but will gradually taper off through the day Tuesday as the cold front fully exits the state by the evening time frame. The low by 12z Wednesday will be a chilly 40°F due to the absence of significant cloud cover and the cold front bringing a dry-Canadian airmass into the region.  

-Bean, Carrier, Aldrich