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000 FXUS63 KDVN 212338 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 638 PM CDT Tue Jul 21 2026KEY MESSAGES
- Cooler and less humidity this week, with heat returning this weekend with mainly dry conditions through the weekend.
SHORT TERM /THROUGH TONIGHT/
Issued at 312 PM CDT Tue Jul 21 2026
Northwest flow aloft and high pressure building into the area. Skies should clear overnight with drier and cooler air moving into the forecast area. This should result in low temperatures tonight into the mid 50s to lower 60s and winds shifting around to the north to northeast.
LONG TERM /WEDNESDAY THROUGH MONDAY/
Issued at 312 PM CDT Tue Jul 21 2026
A northwest flow pattern remains in place through much of the period with a broad flat ridge building through the intermountain west through late week. The ridge begins to build slightly further east into the central US into the weekend. A weak shortwave will drop southeastward through the area late Thursday and bring a chance for some showers and thunderstorms, with mainly dry conditions otherwise across the area.
Much cooler air aloft will keep temperatures cooler and below the seasonal averages through the end of the week. Thermal ridging builds eastward into the area with H85 temperatures increasing back into the mid to upper 20s Celsius by this weekend with the heat returning to the area. Southerly flow off the Gulf returns by late Sunday into early next week should allow the humidity to return as well.
AVIATION /00Z TAFS THROUGH 00Z THURSDAY/
Issued at 629 PM CDT Tue Jul 21 2026
Gusty northwest winds will come to an end by 01 UTC as the atmosphere decouples and high pressure slowly builds into the area. Winds will be northerly around 5 knots overnight before turning to the northwest after 15 UTC Wednesday with speeds of 5 to 10 knots. Conditions are forecast to remain VFR through the period. Diurnal cumulus will redevelop after 15 UTC and continue through the reminder of the period.
DVN WATCHES / WARNINGS / ADVISORIES
IA...None. IL...None. MO...None.
SHORT TERM...MJB LONG TERM...MJB AVIATION...Cousins