811
FXUS63 KIWX 240539
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
139 AM EDT FRI JUL 24 2026
KEY MESSAGES
- GRADUALLY WARMER OVER THE NEXT SEVERAL DAYS. HOT AND HUMID WITH
HIGHS IN THE UPPER 80S TO LOW 90S BY SUNDAY AND MONDAY.
- PRIMARILY DRY THIS WEEKEND BUT THERE ARE 20-30% CHANCES FOR RAIN
AND STORMS SUNDAY EVENING INTO SUNDAY NIGHT.
- SEVERAL ROUNDS OF RAIN AND STORMS POSSIBLE LATE SUNDAY THROUGH
EARLY TUESDAY. SEVERE WEATHER IS POSSIBLE BUT LOW CONFIDENCE
AT THIS TIME.
DISCUSSION
ISSUED AT 137 AM EDT FRI JUL 24 2026
SATELLITE IMAGERY AND RECENT SURFACE OBSERVATIONS SHOW HIGH CLOUDS
DRIFTING IN FROM THE WEST AS HIGH PRESSURE REMAINS OVERHEAD. IT IS
NOT OUT THE QUESTION THAT SPRINKLES COULD OCCUR TODAY (MAINLY THIS
MORNING AND AFTERNOON) AS MORE CLOUDS ADVECT IN, BUT THE OVERALL
TREND CONTINUES TO BE DRY AND GRADUALLY WARMER THROUGH AT LEAST THE
FIRST HALF OF THE WEEKEND AS THE AIRMASS OVERHEAD MODERATES. HIGHS
WILL BE IN THE UPPER 70S AREA-WIDE TODAY WITH LOW HUMIDITY. WINDS
SHIFT TO BECOME SOUTHWESTERLY ON SATURDAY WITH WAA STARTING TO RAMP
UP. SATURDAY WILL BE SLIGHTLY WARMER AND A BIT HUMID WITH HIGHS IN
THE LOW TO MID 80S AND DEWPOINTS AROUND 60 DEGREES.
HOT AND HUMID BY SUNDAY AND MONDAY WITH INCREASING CHANCES FOR RAIN
AND STORMS. DEWPOINTS CONTINUE TO CLIMB SUNDAY AND MONDAY INTO THE
LOW TO MID 70S WITH WEST/SOUTHWEST FLOW AT THE SURFACE. INCREASED
EVAPOTRANSPIRATION FROM CROPS MAY ALSO AID IN LOCALLY HIGHER
DEWPOINTS. HIGH TEMPERATURES WILL BE IN THE UPPER 80S TO LOW 90S
BOTH DAYS WITH CONTINUED WAA AHEAD OF A COLD FRONT THAT COMES
THROUGH LATE MONDAY/EARLY TUESDAY. OUR FORECAST AREA WILL BE ON THE
FRINGES OF A LARGE UPPER LEVEL RIDGE OVER THE CENTRAL CONUS. THIS IS
A FAVORABLE SUMMERTIME SET UP FOR A POTENTIALLY ACTIVE PATTERN INTO
EARLY NEXT WEEK WITH NORTHWEST FLOW ALOFT. GUIDANCE IS TRENDING
TOWARDS OUR FORECAST AREA BEING IN THE 'RING OF FIRE' WITH THE LARGE
UPPER LEVEL RIDGE CENTERED OVER THE CENTRAL CONUS AND REPEATED
COMPLEXES OF STORMS (MCSS) THAT RIDE THE PERIPHERY OF THE RIDGE.
CONSIDERABLE UNCERTAINTY REMAINS THIS FAR OUT ON TIMING, TRACK, AND
INTENSITY OF STORMS, SO CONFIDENCE IS LOW. A PATTERN LIKE THIS IS
VERY DIFFICULT TO FORECAST FOR MORE THAN 24 HOURS OUT, AS IT TAKES
KNOWING WHEN AND WHERE AN MCS WILL DEVELOP TO UNDERSTAND HOW IT MAY
EVOLVE AND WHERE IT WILL TRACK. SEVERAL ROUNDS OF THUNDERSTORMS MAY
OCCUR SUNDAY EVENING THROUGH MONDAY, BUT EXACT DETAILS ARE SPARSE
AND SUBJECT TO CHANGE. SUNDAY IS TRENDING MAINLY DRY AT THIS TIME,
WITH 20-30% CHANCES FOR STORMS LATE IN THE EVENING. THE BETTER
CHANCES ARRIVE MONDAY AFTERNOON AND EVENING AHEAD OF AND ALONG THE
APPROACHING COLD FRONT. I CAN'T RULE OUT ISOLATED STRONG TO SEVERE
STORMS SUNDAY EVENING, BUT THE BETTER CHANCES AND MORE FAVORABLE
ENVIRONMENT FOR SEVERE WEATHER APPEARS TO BE MONDAY.
OUR ENTIRE FORECAST AREA IS INCLUDED IN THE 15% SEVERE
RISK BY SPC ON MONDAY, JULY 27TH. THE GFS AND ECMWF ARE IN ALIGNMENT
ON A FAVORABLE SYNOPTIC SETUP WITH NORTHWEST FLOW ALOFT AND AN
INCREASING LLJ ON MONDAY. A SERIES OF 500 MB SHORTWAVES WILL
MOVE THROUGH MONDAY, PROVIDING SUFFICIENT LIFT FOR STORM
DEVELOPMENT IN CONJUNCTION WITH THE COLD FRONT. SHEAR AND
INSTABILITY REMAIN THE KEY INGREDIENTS I HAVE THE LEAST
CONFIDENCE IN THIS FAR OUT; WITH HOW HOT AND HUMID IT WILL BE, I
WOULD NOT BE SURPRISED IF INSTABILITY REACHES 3000-4000 J/KG
SBCAPE ON SUNDAY AND MONDAY. BULK SHEAR APPEARS TO BE DECENT
TOO ON MONDAY AT AROUND 30 TO 40 KTS. UNCERTAINTY REMAINS IN
EXACT TIMING, COVERAGE, AND INTENSITY OF STORMS. GIVEN THE
HIGHLY CONDITIONAL SETUP, CONFIDENCE REMAINS LOW OVERALL.
TUESDAY'S WEATHER IS UNCERTAIN, AS IT WILL DEPEND ON WHAT HAPPENS
LATE SUNDAY AND MONDAY. ENSEMBLE GUIDANCE FAVORS DRY AND SEASONABLE
CONDITIONS WITH HIGH PRESSURE BUILDING ONCE AGAIN OVER THE GREAT
LAKES. FOR NOW, WILL STICK WITH DRY CONDITIONS AND HIGHS IN THE MID
80S.
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
ISSUED AT 1248 AM EDT FRI JUL 24 2026
HIGH PRESSURE OVERHEAD CONTINUES TO KEEP CONDITIONS DRY.
SATELLITE IMAGERY AND OBSERVATIONS SHOW HIGH LEVEL CLOUDS MOVING
IN. SKIES WILL BE PARTLY TO MOSTLY CLOUDY TODAY, BUT VFR
CEILINGS ARE EXPECTED TO PREVAIL. WINDS WILL BE LIGHT AND
VARIABLE THROUGH THIS AFTERNOON AND EVENING.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...NONE.
DISCUSSION...JOHNSON
AVIATION...JOHNSON
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