373
FXUS63 KDVN 230819
AFDDVN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
319 AM CDT MON JUN 23 2025
KEY MESSAGES
- DANGEROUSLY HOT AND HUMID CONDITIONS WILL PERSIST THROUGH AT LEAST
TODAY, AND POSSIBLY THROUGH TUESDAY IN THE SOUTH. A HEAT ADVISORY
REMAINS IN EFFECT THROUGH 8 PM MONDAY.
- AN ACTIVE PATTERN RETURNS TO THE AREA FOR THE UPCOMING WEEK
WITH NEAR DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS. SOME
STRONG TO SEVERE STORMS AND HEAVY RAINFALL WILL BE POSSIBLE AT
TIMES.
SHORT TERM /THROUGH TONIGHT/
ISSUED AT 310 AM CDT MON JUN 23 2025
EARLY MORNING ANALYSIS PLACES A COLD FRONT EXTENDING FROM N MN
TO A WEAK LEE LOW IN SW NE/FAR NW KS. REGIONAL RADAR MOSAIC SHOWS
SOME AREAS OF CONVECTION ALONG AND NORTH OF THE FRONTAL ZONE
WITH THE MORE ROBUST ACTIVITY /TRAILING STRATIFORM MCS/ ACROSS
SE SD INTO NC/NE NE. THE NORTHERN PORTION OF THE FRONT (MN/WI/MI)
WILL HAVE MORE OF A PUSH RESIDING BENEATH STRONGER MID LEVEL
FLOW, WHILE THE SOUTHERN PORTION (IA/NE) WILL MOVE MUCH SLOWER
BEING FURTHER DISPLACED FROM THE STRONGER FLOW AND MORE PARALLEL
TO THE UPPER FLOW. THIS WILL LEAD TO A SAGGING BOUNDARY INTO THE
AREA LATE TODAY AND ESPECIALLY TONIGHT FACILITATING A BURGEONING
OF SHOWER/STORM CHANCES. GREATEST COVERAGE (IN ABSENCE OF COOL
POOL/OUTFLOWS) LOOKS TO FAVOR AREAS PARTICULARLY NORTH/WEST OF
THE QC METRO RESIDING NEAR TO NORTH OF THE FRONTAL ZONE IN TIME.
FORECAST SOUNDINGS AHEAD OF THE FRONT SUPPORT A VERY UNSTABLE
ENVIRONMENT WITH SBCAPE OF 2500-3000+ J/KG (BASED ON AROUND 90F/70F
T/TD). SHEAR PROFILES REMAIN UNIDIRECTIONAL AND PARALLEL TO THE
BOUNDARY. IN ADDITION DEEP LAYER SHEAR DOESN'T LOOK OVERLY
STRONG AT AROUND 20-25 KTS WITH MUCH OF THAT INCREASE IN THE
LOWEST 1-3KM. ALL OF THIS LENDS SUPPORT TO THE SEVERE POTENTIAL
BEING PRIMARILY MULTICELL STORM CLUSTERS WITH AN ATTENDANT
DAMAGING WIND THREAT, ESPECIALLY WHEN FACTORING IN VERY HIGH DCAPE
PROGGED AT NEAR 1200 J/KG. SPC'S SLIGHT RISK (LEVEL 2 OUT OF 5)
AREA LOOKS REASONABLE ROUGHLY ALONG AND NORTHWEST OF A FREEPORT, IL
TO WASHINGTON, IA LINE. THINKING THE TIMING OR MAIN WINDOW FOR
SEVERE WEATHER IS ROUGHLY 4 PM TO 10 PM, WITH A WANING IN INTENSITY
GENERALLY LATER AT NIGHT HEADING TOWARD DIURNAL MINIMUM. IN
ADDITION TO THE SEVERE RISK, HEAVY RAIN AND LOCALIZED FLOODING IS
ALSO A CONCERN WITH THE 850-300 HPA MEAN FLOW PARALLEL TO THE BOUNDARY
FOSTERING A FAVORABLE SETUP FOR CELL TRAINING/REPEATED ACTIVITY
AMIDST AN ANOMALOUS MOISTURE PLUME (PWATS SURGING TO NEAR 2 INCHES -
NEAR THE DAILY MAX FOR ALL DVN RAOBS ON JUNE 23 PER SPC SOUNDING
CLIMATOLOGY). 00Z HREF ENSEMBLE MEAN SHOWS 1-2" AMOUNTS IN THIS
AFOREMENTIONED AREA FOR THE 24 HOUR PERIOD ENDING 12Z TUESDAY, WITH
THE LOCALIZED PROBABILITY MATCHED MEAN (LPMM) DEPICTING A SIGNAL
FOR SOME AREAS OF HIGHER AMOUNTS OF 3+ INCHES. WOULD LEAD TO A
GREATER CONCERN FOR FLOODING IF THIS WERE TO OCCUR OVER AN URBAN AREA.
CONFIDENCE REMAINS HIGH THAT MUCH OF THE AREA WILL SEE AT LEAST ONE
MORE DAY OF DANGEROUS HEAT TODAY WITH HIGHS BACK IN THE 90S AND
HEAT INDEX READINGS 100 TO AROUND 105F, THUS THE HEAT ADVISORY REMAINS
IN EFFECT UNTIL 8 PM THIS EVENING. IT'S POSSIBLE THAT INCREASING
CLOUDS AND THE DEVELOPING RAIN CHANCES LATER THIS AFTERNOON COULD MAKE
REACHING CRITERIA MORE MARGINAL FOR SOME LOCATIONS NORTHWEST OF
CEDAR RAPIDS TO DUBUQUE. WE'RE ALSO EXPECTING ANOTHER DAY OF GUSTY
WINDS OF 20-30+ MPH, WHICH MAY CONTINUE TO OFFER SOME MINOR RELIEF.
LONG TERM /TUESDAY THROUGH SUNDAY/
ISSUED AT 310 AM CDT MON JUN 23 2025
TUESDAY INTO NEXT WEEKEND LOOKS TO REMAIN ACTIVE/UNSETTLED WITH THE
FRONTAL BOUNDARY MEANDERING IN OR NEAR THE AREA, WHILE ALOFT ALSO
RESIDING ON THE EDGE OF STRONGER SOUTHWESTERLY MID LEVEL FLOW
SHUTTLING PERIODIC DISTURBANCES THROUGH THE REGION. THIS WILL RESULT
IN EPISODES OF SHOWERS AND STORMS AT TIMES. TRYING TO PIN DOWN EXACT
PLACEMENT AND TIMING OF THE GREATEST RAIN CHANCES IS EXCEEDINGLY
DIFFICULT IN THIS REGIME. HOWEVER, WHEREVER THE BOUNDARY RESIDES WILL
LOOK TO SERVE AS THE FOCUS FOR SOME STRONG TO POSSIBLY SEVERE STORMS
AND HEAVY RAIN POTENTIALLY AT TIMES. SOME OF OUR NORTHERN TRIBUTARY
RIVERS (CEDAR/IOWA/WAPSIPINICON) ARE EXPERIENCING RISES FROM RECENT
HEAVY RAINS IN THE HEAD WATERS, AND SO THIS WILL BEAR WATCHING
THROUGHOUT THE WEEK AS DEPENDING ON WHERE THE HEAVY RAIN LAYS OUT
THESE RIVERS COULD BE MORE SUSCEPTIBLE TO FLOODING WITH ALREADY HIGH
FLOWS. OTHERWISE, IT LOOKS TO BE QUINTISSENTIAL JUNE WITH VERY WARM/
HOT AND MUGGY CONDITIONS THROUGHOUT THE PERIOD, WHICH MAY ACTUALLY
FEEL MORE OPPRESSIVE THAN OUR CURRENT HEAT WAVE GIVEN THE ADDED
MOISTURE FROM RAINFALL JUICING THE BOUNDARY LAYER DEW POINTS WHILE
A WEAKER FLOW REGIME PROMOTES A MORE STAGNANT AIRMASS. CAN'T RULE OUT
SOME AREAS NEAR ADVISORY LEVEL HEAT INDEX READINGS OF 100+ AT TIMES,
PARTICULARLY SOUTHERN AREAS ON TUESDAY, AND THEN PERHAPS EXPANDING
AGAIN MIDWEEK AREA-WIDE, BUT THERE'S TOO MUCH UNCERTAINTY WITH THE
BOUNDARY PLACEMENT AND POTENTIAL IMPACTS FROM PRECIPITATION/CLOUDS TO
EXTEND THE CURRENT HEAT HEADLINES.
AVIATION /06Z TAFS THROUGH 06Z TUESDAY/
ISSUED AT 1125 PM CDT SUN JUN 22 2025
LLWS IS EXPECTED THROUGH DAYBREAK WITH SSW SURFACE WINDS AROUND
10 KTS WHILE WINDS ALOFT NEAR 2KFT AGL INCREASE TO 40-50 KTS.
SURFACE WINDS WILL TURN GUSTY AGAIN AFTER DAYBREAK ON MONDAY
WITH GUSTS 20-30 KTS. A FRONT WILL APPROACH NORTHEAST IOWA
MONDAY AFTERNOON, AND WILL SERVE AS THE FOCUS FOR SHOWERS AND
STORMS LATE MONDAY AFTERNOON THROUGH EVENING. HIGHEST CONFIDENCE
ON PRECIPITATION IS AT CID AND DBQ (50-70%) BEING IN CLOSER
PROXIMITY TO THE BOUNDARY, AND THEREFORE HAVE GONE WITH TEMPO
AND PREVAILING MENTION AT BOTH SITES. CONFIDENCE DECREASES WITH
SOUTHWARD EXTENT TO MLI (PROB30 MENTION MONDAY EVENING) AND BRL
(20% OR LESS MONDAY EVENING WARRANTS NO MENTION AT THIS TIME).
CONDITIONS WILL DROP TO MVFR WITH LOCAL IFR IN THE STRONGER
SHOWERS AND STORMS. GUSTY ERRATIC WINDS WILL ALSO BE FOUND IN/
AROUND ANY STORMS. OUTSIDE OF ANY PRECIPITATION VFR CONDITIONS
WILL DOMINATE.
CLIMATE
ISSUED AT 313 AM CDT MON JUN 22 2025
RECORD HIGH TEMPERATURES:
JUNE 23:
KBRL: 100/1911
KCID: 100/1931
KDBQ: 96/1923
KMLI: 97/1931
RECORD WARM LOW TEMPERATURES:
JUNE 23:
KDBQ: 79/1874
KMLI: 77/1950
DVN WATCHES/WARNINGS/ADVISORIES
IA...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR IAZ040>042-
051>054-063>068-076>078-087>089-098-099.
IL...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR ILZ001-002-007-
009-015>018-024>026-034-035.
MO...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR MOZ009-010.
SHORT TERM...MCCLURE
LONG TERM...MCCLURE
AVIATION...MCCLURE
CLIMATE...MCCLURE
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