842
FXUS01 KWBC 200749
PMDSPD
SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
348 AM EDT MON JUL 20 2026
VALID 12Z MON JUL 20 2026 - 12Z WED JUL 22 2026
...HIGH CONCENTRATIONS OF CANADIAN WILDFIRE SMOKE TO AFFECT THE
GREAT LAKES AREA OVER THE NEXT FEW DAYS...
...A STRONG SOUTHEASTWARD MOVING FRONTAL SYSTEM TO SUPPORT ACTIVE
THUNDERSTORMS FROM THE NORTHERN PLAINS TO THE MID-ATLANTIC...
...T.D. TWO TO BRING HEAVY RAIN THREATS TO THE NORTHEAST GULF
COAST...
...MONSOONAL THUNDERSTORMS TO CONTINUE OVER THE NEXT FEW DAYS FROM
THE SOUTHWEST INTO THE GREAT BASIN...
...HAZARDOUS HEAT BUILDS FROM THE NORTHERN PLAINS INTO THE LOWER
MISSISSIPPI VALLEY...
THERE IS NO LET UP IN AIR QUALITY ISSUES OVER THE NEXT FEW DAYS
DOWNWIND OF THE ONGOING CANADIAN WILDFIRES ACROSS WESTERN PORTIONS
OF ONTARIO. THE LATEST SMOKE MODELS ARE FOCUSING THE HIGHEST
CONCENTRATIONS OF SMOKE ACROSS THE GREAT LAKES TODAY, FOLLOWED BY
ANOTHER SHOT OF SMOKE MOVING SOUTH ON TUESDAY ACROSS THIS AREA IN
THE WAKE OF A STRONG FRONTAL SYSTEM PUSHING EAST. AIR QUALITY
ALERTS ARE CURRENTLY IN EFFECT ACROSS THE GREAT LAKES INTO
PORTIONS OF THE MIDWEST, WITH THIS LIKELY TO CONTINUE OVER THE
NEXT FEW DAYS. AIR QUALITY ISSUES ARE ALSO EXPECTED ACROSS
PORTIONS OF THE PACIFIC NORTHWEST INTO THE NORTHERN ROCKIES DUE TO
WILDFIRES ACROSS THIS AREA. AIR QUALITY ALERTS ARE CURRENTLY IN
EFFECT ACROSS EASTERN OREGON INTO NORTHERN IDAHO.
THE SAME FRONTAL SYSTEM WILL FOCUS WIDELY SCATTERED SEVERE
THUNDERSTORMS AND SOME FLASH FLOODING TODAY AND TOMORROW ACROSS
PORTIONS OF THE MIDWEST, NORTHEAST, AND MID-ATLANTIC. MEANWHILE,
T.D. TWO IS FORECAST TO GRADUALLY STRENGTHEN OVER THE NEXT 48
HOURS AS IT MEANDERS WESTWARD TOWARD THE CENTRAL GULF COAST. MUCH
OF THE PRECIPITATION WITH THIS STORM IS STILL EXPECTED TO REMAIN
JUST OFFSHORE, ALTHOUGH FLASH FLOODING CERTAINLY REMAINS A THREAT
WITH THIS SYSTEM AS THE OUTER BANDS OF T.D. TWO APPROACH THE I-1O
CORRIDOR FROM NORTHWEST FLORIDA TO SOUTHEAST LOUISIANA. SEE THE
LATEST NHC ADVISORIES FOR ADDITIONAL AND UPDATED INFORMATION ON
THIS STORM. IN THE WEST, AN ACTIVE MONSOONAL PATTERN WILL PERSIST
ACROSS THE SOUTHWEST AND GREAT BASIN FOR AT LEAST THE NEXT THREE
DAYS. SCATTERED FLASH FLOODING REMAINS THE FOREMOST CONCERN WITH
THIS ACTIVITY OWING TO THE PLENTIFUL MOISTURE AVAILABLE FOR THE
DAILY THUNDERSTORMS TO TAP INTO.
WHILE COOLER AIR IS EXPECTED BEHIND THE AFOREMENTIONED COLD FRONT,
BUILDING MID TO UPPER-LEVEL HEIGHTS ACROSS THE CENTRAL ROCKIES AND
PLAINS WILL CONTINUE TO SUPPORT MUCH ABOVE AVERAGE TEMPERATURES
EARLY THIS WEEK ACROSS MUCH OF THE PLAINS, LOWER MISSOURI VALLEY,
AND LOWER MISSISSIPPI VALLEY. HEAT INDICES IN THESE REGION ARE
EXPECTED TO APPROACH 110-115 DEGREES TODAY AND TOMORROW, WHERE A
SWATH OF HEAT ADVISORIES ARE IN EFFECT.
ASHERMAN/ORAVEC
GRAPHICS AVAILABLE AT
HTTPS://WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page