654
FXUS63 KDVN 291930
AFDDVN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
230 PM CDT MON JUN 29 2026
KEY MESSAGES
- EXTREME HEAT WARNING CONTINUES THROUGH WEDNESDAY EVENING DUE
TO A PROLONGED PERIOD OF HOT AND VERY HUMID CONDITIONS. DAILY
PEAK HEAT INDEX VALUES OF 100 TO 110 AND NIGHTTIME LOW
TEMPERATURES ONLY DROPPING INTO THE MID 70S.
- INCREASING THUNDERSTORM CHANCES INTO MIDWEEK ONWARD (INCLUDING
THE JULY 4TH WEEKEND), WITH THE RESULTANT CLOUD COVER
POTENTIALLY HAVING AN IMPACT ON HIGH TEMPERATURES. VERY HUMID
CONDITIONS WILL REMAIN.
SHORT TERM /THROUGH TUESDAY NIGHT/
ISSUED AT 230 PM CDT MON JUN 29 2026
UPPER RIDGE TO CONTINUE ACROSS THE CENTRAL AND SOUTHEASTERN US
WITH SOUTHWESTERLY FLOW ACROSS THE PLAINS INTO THE GREAT LAKES.
THIS PATTERN CONTINUES TO ALLOW THE HEAT TO BUILD ACROSS THE
AREA WITH VERY HUMID CONDITIONS AS WELL WITH FLOW OFF THE GULF.
HEAT INDEX VALUES ALREADY INTO 100-105 RANGE OR HIGHER AT MANY
SITES TODAY, AND EVEN WARMER AIR ALOFT EXPECTED TO PUSH INTO THE
AREA TUESDAY. LITTLE RELIEF EXPECTED AT NIGHT WITH THE HUMID
AIRMASS AND WARM TEMPERATURES KEEPING OVERNIGHT TEMPERATURES
DROPPING INTO THE UPPER 70S TO AROUND 80. THE EXTREME HEAT
WARNING WILL CONTINUE WITH THE HEAT EXPECTED THROUGH MIDWEEK.
LONG TERM /WEDNESDAY THROUGH SUNDAY/
ISSUED AT 230 PM CDT MON JUN 29 2026
THE UPPER RIDGE ACROSS THE CENTRAL/SOUTHERN US TO BEGIN TO BREAK
DOWN SOME INTO THE MIDDLE TO END OF THE WEEK ALLOWING THE
SOUTHWESTERLY FLOW ALOFT TO BECOME ORIENTED MORE ACROSS THE
FORECAST AREA. THIS WILL BRING INCREASING CHANCES FOR
THUNDERSTORMS BY WEDNESDAY INTO THE WEEKEND, ESPECIALLY INTO THE
WEEKEND AS THE RIDGE BREAKS DOWN FURTHER WITH A MORE ZONAL FLOW
PATTERN SETTING UP WITH STRONGER SHORTWAVE TROUGHS IMPACTING THE
REGION. THEREFORE THE CONTINUATION OF THE HEAT AND HIGH
TEMPERATURES INTO THE END OF THE WEEK AND THIS WEEKEND ARE
SOMEWHAT UNCERTAIN DEPENDENT ON THUNDERSTORM CHANCES DUE TO
CLOUD COVER AND OVERALL STORM CHANCES, ETC. CONTINUED MOISTURE
FLOW OFF THE GULF REMAINS, SO HUMID CONDITIONS WILL CONTINUE
THROUGH THE FORECAST PERIOD. FOR NOW THE THREAT OF STRONG TO
SEVERE STORMS IS STILL UNCERTAIN FOR ANY ONE PERIOD, HOWEVER THE
PATTERN WOULD SUGGEST MORE ORGANIZATION WITH THE STORM CHANCES
INTO THE WEEKEND WITH THE STRONGER UPPER LEVEL TROUGHS HELPING
FORCE THE STORM CHANCES.
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
ISSUED AT 117 PM CDT MON JUN 29 2026
WINDS AND SOME LOW LEVEL CU THE MAIN ISSUES IN THE TERMINAL
FORECASTS TODAY. GUSTY SOUTHERLY WINDS TODAY, SHOULD BEGIN TO
DIMINISH SOME OVERNIGHT WITH THE GUSTINESS BEFORE PICKING UP
AGAIN INTO TUESDAY. MVFR CU EXPECTED TO LIFT TO LOWER VFR THIS
AFTERNOON, WITH SKIES CLEARING OVERNIGHT, POTENTIALLY SOME VERY
HIGH THIN CIRRUS.
DVN WATCHES/WARNINGS/ADVISORIES
IA...EXTREME HEAT WARNING UNTIL 10 PM CDT WEDNESDAY FOR IAZ040>042-
051>054-063>068-076>078-087>089-098-099.
IL...EXTREME HEAT WARNING UNTIL 10 PM CDT WEDNESDAY FOR ILZ001-002-
007-009-015>018-024>026-034-035.
MO...EXTREME HEAT WARNING UNTIL 10 PM CDT WEDNESDAY FOR MOZ009-010.
SHORT TERM...MJB
LONG TERM...MJB
AVIATION...MJB
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page