637
FXUS61 KILN 201649
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
1249 PM EDT MON JUL 20 2026
WHAT HAS CHANGED
NO SIGNIFICANT CHANGES.
KEY MESSAGES
KEY MESSAGE 1) PATCHY WILDFIRE SMOKE POSSIBLE TODAY.
KEY MESSAGE 2) A STRONG COLD FRONT WILL MOVE THROUGH THE REGION ON
TUESDAY. THIS WILL BRING A CHANCE FOR THUNDERSTORMS INTO TUESDAY
EVENING AND THEN DRIER AND SOMEWHAT COOLER CONDITIONS FOR MID TO
LATE WEEK.
DISCUSSION
KEY MESSAGE 1)
THE 00Z HRRR NEAR SURFACE SMOKE DENSITY FIELD IS SHOWING ONE LAST
ROUND OF HIGHER SMOKE DENSITIES ROTATING WESTWARD ACROSS OUR AREA
THIS MORNING, MAINLY AFFECTING NORTHERN PORTIONS OF THE AREA. AS THE
FLOW BECOMES MORE SOUTHERLY THROUGH THE DAY, THE AREA OF SMOKE WILL
THEN BE PUSHED BACK OFF TO OUR NORTH THROUGH THIS AFTERNOON. THE
DENSITY VALUES ARE STILL NOT AS HIGH AS THEY WERE LATE LAST WEEK SO
WILL GENERALLY JUST ALLOW FOR SOME PATCHY SMOKE IN THE FORECAST
TODAY.
KEY MESSAGE 2)
A SEASONABLY STRONG MID LEVEL SHORT WAVE WILL DROP DOWN ACROSS THE
WESTERN GREAT LAKES TONIGHT AND INTO THE MID/UPPER OHIO VALLEY
THROUGH THE DAY ON TUESDAY. THIS WILL BE ACCOMPANIED BY A 30-40 KNOT
850 MB JET THAT WILL WORK ITS WAY SOUTHEASTWARD ACROSS OUR AREA
THROUGH THE DAY. MEANWHILE, SOUTHWEST LOW LEVEL FLOW AHEAD OF THIS
WILL LEAD TO DECENT MOISTURE ADVECTION UP INTO THE REGION WITH
SURFACE DEWPOINTS MOVING BACK INTO THE LOW TO POSSIBLY MID 70S.
THERE IS SOME UNCERTAINTY WITH THE POTENTIAL FOR REMNANTS OF AN MCS
DROPPING DOWN TOWARD/INTO OUR AREA LATE TONIGHT INTO TUESDAY MORNING
AND WHAT EFFECTS THIS COULD HAVE ON OUR TEMPERATURES THROUGH THE DAY.
ASSUMING THAT WE ARE STILL ABLE TO RECOVER ENOUGH FROM THIS, GOOD
INSTABILITY WILL DEVELOP THROUGH THE AFTERNOON. THIS WOULD LEAD TO
DEVELOPING SHOWERS AND THUNDERSTORMS, POSSIBLY INITIATING ALONG A
RESIDUAL BOUNDARY FROM THE EARLIER MCS. THE STORMS WOULD THEN DROP
SOUTHEAST ACROSS THE REMAINDER OF OUR AREA THROUGH THE AFTERNOON,
POSSIBLY INTO EARLY EVENING. WITH SEASONABLY STRONG DEEP AND 0-3 KM
SHEAR PRESENT, SOME SEVERE STORMS WOULD SEEM LIKELY. DAMAGING WIND
REMAINS THE MAIN THREAT BUT LARGE HAIL AND AN ISOLATED TORNADO WOULD
ALSO BE POSSIBLE. HIGH PWS WILL ALSO LEAD TO THE POTENTIAL FOR
LOCALLY HEAVY RAINFALL/ISOLATED FLASH FLOODING. BASED ON THE TIMING,
THE BEST CHANCE FOR SEVERE WEATHER WOULD LIKELY BE ACROSS ABOUT THE
SOUTHEAST TWO THIRDS OF OUR AREA THROUGH TUESDAY AFTERNOON/EARLY
EVENING.
THE COLD FRONT WILL MOVE SOUTHEAST OF THE AREA TUESDAY NIGHT,
USHERING IN A DRIER AND COOLER AIRMASS FOR MID TO LATE WEEK.
AVIATION /18Z MONDAY THROUGH SATURDAY/
GENERALLY VFR CONDITIONS ARE EXPECTED THROUGH THE REST OF THE DAY,
ALTHOUGH SOME SMOKE COULD REDUCE VISIBILITIES THROUGH THIS AFTERNOON,
AND OCCASIONAL MVFR CONDITIONS ARE POSSIBLE.
LATE OVERNIGHT INTO EARLY TUESDAY MORNING, SHOWERS AND THUNDERSTORMS
ARE EXPECTED TO MOVE INTO THE AREA FROM THE NORTH. THIS HAS BEEN
INDICATED IN THE TAFS WITH A PREVAILING -SHRA AND PROB30 -TSRA
MENTION, THOUGH TIMING AND CONFIDENCE WILL KEEP THE -TSRA MENTION OUT
OF THE CINCINNATI TAF SITES FOR NOW. SOME MVFR CEILINGS ARE
POSSIBLE TUESDAY MORNING, EVEN OUTSIDE OF ANY THUNDERSTORMS.
ADDITIONAL THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE TUESDAY
AFTERNOON, THOUGH CONFIDENCE IN SPECIFICS IS VERY LOW, AS IT WILL BE
DEPENDENT ON HOW THINGS GO WITH THE THUNDERSTORMS IN THE MORNING.
OUTLOOK...THUNDERSTORMS LIKELY TUESDAY AFTERNOON INTO TUESDAY
EVENING.
ILN WATCHES/WARNINGS/ADVISORIES
OH...AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR OHZ042-043-051-053-
060>062.
AIR QUALITY ALERT UNTIL 9 PM EDT THIS EVENING FOR OHZ046-055-056-
065.
KY...NONE.
IN...AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR INZ050-058-059-066.
DISCUSSION...JGL
AVIATION...HATZOS
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