845
FOCN45 CWWG 161900
SIGNIFICANT WEATHER DISCUSSION ISSUED BY THE PRAIRIE AND ARCTIC STORM
PREDICTION CENTRE OF ENVIRONMENT CANADA AT 2:00 PM CDT WEDNESDAY JULY
16 2025.
ALERTS IN EFFECT...AIR QUALITY ALERTS FOR PARTS OF ALBERTA,
SASKATCHEWAN, MANITOBA, AND NWT. FOG ADVISORY FOR IGLOOLIK. HEAT
WARNING FOR THE FT. SMITH REGION.
SYNOPTIC OVERVIEW...ALOFT, A LARGE UPPER LOW SITS OVER THE NORTHERN
TIP OF QUEBEC WITH TROUGHING NORTH TO THE POLE, EAST OVER THE
LABRADOR SEA, AND SOUTHWEST ACROSS MANITOBA. AN UPPER RIDGE
CONTINUES TO PROGRESS EASTWARD OVER THE WESTERN ARCTIC, BUT NOT OVER
BC, WHERE AN UPPER LOW IS DEVELOPING OVER THE CENTRE OF THE PROVINCE
AND IS TRACKING SOUTHEAST.
AT THE SURFACE, A 1014 MB LOW IS DEVELOPING OVER WESTERN AB. A 1026
MB HIGH SITS NEAR REGINA, WITH RIDGING NORTHWARD THROUGH THE CENTRAL
ARCTIC AND EASTWARD INTO NORTHWESTERN ONTARIO. TO THE NORTHEAST, A
993 MB LOW CONTINUES TO DECAY NEAR KINNGAIT. IN THE WEST, A WEAK
1014 MB LOW SITS OVER THE ARCTIC OCEAN WITH TROUGH TO SACHS HARBOUR.
OTHER THAN A WARM FRONT PUSHING EAST ACROSS THE NWT, ALL OTHER
SURFACE FRONTS HAVE DEPARTED THE AOR.
DISCUSSION...
PRAIRIES...BOUNDARY LAYER DECOUPLING SAW AQHI VALUES SPIKE OVER
SOUTHWESTERN SK AGAIN LAST NIGHT AS SMOKE CONCENTRATED NEAR THE
SURFACE. EVEN SO, THE GENERAL TREND FOR THE AREA WILL BE GRADUAL
IMPROVEMENT TODAY AS WINDS TURN SOUTHERLY. CURRENT IN-PLACE SMOKE
WILL PUSH BACK NORTHWARD OR BE DISPERSED VERTICALLY MORE THROUGH THE
DAY, WHILE NEW PLUMES FROM THE MAJOR FIRES ARE DIRECTED MORE TO THE
NORTH AND EAST - THOUGH ONLY WEAKLY. WILL NEED TO MONITOR THE AB/SK
CENTRAL BORDER AREA FOR UPGRADES TO WARNINGS SHOULD THE NEED ARISE,
BUT OTHERWISE SLOW PARING BACK IN THE SOUTH SHOULD BE THE ORDER OF
THE DAY.
FURTHER TO THE NORTH IN SK, SMOKE WILL CONTINUE TO BE AN ISSUE
THROUGH MANY AREAS. WITH LITTLE FLOW TO WORK WITH, THE AQW'S WILL
REMAIN IN EFFECT FOR THE NEXT DAY OR SO BEFORE THE PATTERN SHIFTS.
FOR THE SOUTHEAST CORNER OF MANITOBA, WINDS HAVE TURNED A LITTLE
MORE NORTHEASTERLY THROUGH THE NIGHT, AND ANOTHER PLUME FROM THE
FIRES EAST OF LAKE WINNIPEG IS TRACKING TOWARDS THE RRV. SAQS HAVE
BEEN SHIFTED EASTWARD WITH THE PLUME, AND WILL LIKELY FURTHER EXTEND
EASTWARD THROUGH THE DAY.
LONGER TERM FOR THE SOUTHERN PRAIRIES, SMOKE CONCERNS WILL
CONSOLIDATE TOWARDS THE FIRE SOURCE REGIONS OVER THE COMING DAYS
WITH A BROAD HIGH ACROSS THE SOUTH; THIS COULD CAUSE ANOTHER
WIDESPREAD SMOKE ISSUE IN THE DAYS AHEAD IF THE SMOKE CAN BUILD UP
UNDER THE RIDGE THEN IS SHIFTED WITH THE FLOW, BUT WE'LL HAVE TO
WAIT AND SEE.
IN NORTHERN MANITOBA, SMOKE ISSUES REMAIN RATHER LOCALIZED AFTER A
COUPLE OF COOLER DAYS, BUT MORE SEASONAL TEMPERATURES ARE RETURNING.
OTHER THAN A CHANCE OF ISOLATED NON-SEVERE THUNDERSTORMS TODAY AND
WEDNESDAY, SKIES WILL BE MORE SUNNY THAN NOT AND TEMPERATURES WILL
BE BACK NEAR THE 30 DEGREE MARK BY THE END OF THE WEEK. AND, SOME
SMOKE FROM SK IS LIKELY TO EVENTUALLY MAKE IT INTO THE AREA AS WELL.
TURNING OUR ATTENTION TO THE THUNDERSTORM RISK FOR TODAY, THE
MAIN CONCERN FOR THUNDERSTORMS WILL BE CONFINED TO CLOSER TO THE
AB-B.C. BORDER, WHERE SUFFICIENT MLCAPE VALUES COMBINED WITH THE
UPPER LOW AND WEAK SHEAR ENVIRONMENT WILL GENERATE SLOW-MOVING
STORMS, WITH AMPLE PRECIPITATION POTENTIAL AND THE POSSIBILITY OF
FUNNEL CLOUDS CLOSER TO THE AB ELBOW. SOUTH OF THE FUNNEL CLOUD
AREA, STRONGER SHEAR IS FORECAST WHICH COULD ENHANCE THE POSSIBILITY
OF STORMS IN THIS AREA BEING LONGER-LIVED WITH THE CAPABILITY OF
GENERATING HAIL. THIS AREA IS DENOTED AS 'B' ON THE THUNDERSTORM
OUTLOOK. SIMILAR STORY FOR TOMORROW, JUST SHIFTED SOUTH.
NT...A FEW THINGS TO NOTE FOR THIS REGION. TO START, AS ALWAYS SMOKE
FORECASTING IS DIFFICULT TO BE PRECISE. AIR QUALITY WARNINGS ARE
CURRENTLY IN EFFECT FOR AREAS NORTH AND WEST OF GREAT SLAVE LAKE AND
WILL REMAIN SO FOR AT LEAST SOME AREAS TODAY AND LIKELY THROUGH
TONIGHT AS WELL.
THUNDERSTORMS ARE ONCE AGAIN FORECAST THROUGH MUCH OF THE WEST.
STORMS WILL BE SLOW MOVING AND THERE IS SOME POTENTIAL FOR LOCALLY
HEAVY RAIN. BEST CHANCE TODAY FROM ROUGHLY THE LIARD REGION TO
WESTERN GREAT BEAR LAKE, WHERE THE BEST CAPES ARE EXPECTED THIS
AFTERNOON. FURTHER EAST COULD SEE SOME GUSTY WINDS IN HIGH BASED
STORMS. THUNDERSTORMS WILL CONTINUE THROUGH TOMORROW ALONG AN
EASTWARD MOVING TROUGH/COLD FRONT.
TEMPERATURES IN FORT SMITH WILL BE CLOSE TO OR WITHIN THE HEAT
WARNING CRITERIA OVER THE NEXT SEVERAL DAYS. NEARBY REGIONS WILL
ALSO BE CLOSE, ESPECIALLY FOR AREAS FURTHER AWAY FROM GREAT SLAVE
LAKE (CONDITIONS WILL BE A BIT COOLER NEAR THE LAKE SHORE).
NU...THE SYSTEM NEAR KINNGAIT CONTINUES TO DECAY WITH JUST A FEW
SHOWERS LINGERING AROUND BAFFIN ISLAND AND KIVALLIQ. WITH WEAK FLOW
SETTLING OVER THE AREA, REMNANT CLOUD, DRIZZLE, AND FOG WILL BE THE
MAIN ISSUES FOR THE NEXT FEW DAYS.
END/KNIGHT/MOODIE/ROMBOUGH
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