130
FOCN45 CWWG 301900
SIGNIFICANT WEATHER DISCUSSION ISSUED BY THE PRAIRIE AND ARCTIC STORM
PREDICTION CENTRE OF ENVIRONMENT CANADA AT 2:00 PM CDT TUESDAY JUNE
30 2026.
ALERTS IN EFFECT...RAINFALL WARNING FOR WESTERN MANITOBA. HEAT AND
AIR QUALITY WARNINGS FOR SOUTHERN NT, NORTHERN SASKATCHEWAN AND
PORTIONS OF ALBERTA.
OVERVIEW...ALOFT TODAY, A WEAK UPPER LOW SITS OVER CENTRAL BRITISH
COLUMBIA, EMBEDDED IN A LARGER UPPER TROUGH THAT EXTENDS FROM ALASKA
TO NORTHERN BRITISH COLUMBIA THEN SOUTH THROUGH BC. EAST OF
THIS, A VIGOROUS UPPER LOW SITS OVER SOUTHERN MANITOBA'S INTERLAKE
REGION WITH A LONG-WAVE TROUGH WEST ACROSS SOUTHERN SASKATCHEWAN.
NORTH OF THIS, AN UPPER HIGH SITS ALONG THE NORTHWEST
TERRITORIES/NUNAVUT BORDER WITH RIDGING NORTH INTO THE CANADIAN
ARCTIC ARCHIPELAGO. EAST OF THIS, A COUPLE SHORTWAVES ARE SLUMPING
THROUGH THE EASTERN ARCTIC; ONE OVER BAFFIN BAY, ANOTHER NEAR THE
UNGAVA PENINSULA, AND ANOTHER EXITING DAVIS STRAIT INTO THE LABRADOR
SEA.
AT THE SURFACE, A 990 MB LOW SITS OVER MANITOBA'S INTERLAKE REGION
WITH A TROUGH NORTHEAST TO A FRONTAL WAVE WITH APEX NEAR ISLAND
LAKE, MB; IT HAS A COLD FRONT THAT SWEEPS SOUTH THROUGH ONTARIO INTO
MINNESOTA AND A WARM FRONT THAT'S DRAPED EAST-SOUTHEAST ACROSS
ONTARIO INTO SOUTHERN QUEBEC. A SURFACE TROUGH EXTENDS WESTWARD FROM
THE LOW ACROSS SOUTHERN SASKATCHEWAN. IN THE NORTH, A 1000 MB LOW
SITS NORTH OF VICTORIA ISLAND WITH A WARM FRONT THAT DROPS
SOUTH-SOUTHEAST INTO THE KIVALLIQ AND A COLD FRONT THAT HANGS
SOUTHWEST INTO YUKON. A WARM-SECTOR TROUGH DROPS SOUTH THROUGH
NORTHWEST TERRITORIES INTO ALBERTA. MOVING EAST, A 1016 MB HIGH SITS
NEAR THE MELVILLE PENINSULA WITH RIDIGNG INTO HUDSON BAY AS WELL AS
OVER NORTHERN BAFFIN ISLAND.
DISCUSSION...
AB/NRN SK...A SPLIT FLOW REMAINS IN THE REGION WITH EASTERLIES OVER
NORTHERN SASKATCHEWAN BECOMING NORTHWESTERLIES OVER SOUTHERN ALBERTA
AND SOUTHERLIES OVER NORTHERN ALBERTA. THIS HAS FUNNELED SMOKE FROM
THE NUMEROUS FIRES FROM THE EASTERN PRAIRIES INTO ALBERTA.
AIR QUALITY HAS GENERALLY BEEN HOVERING IN THE MODERATE TO HIGH RISK
RANGE OVER AREAS WHERE THE WARNING IS OUT. THE FLOW WILL
SLACKEN AND IMPROVE THE AIR QUALITY OVER THE NEXT COUPLE DAYS,
WITH THE EXCEPTION OF NORTHERN SASKATCHEWAN WHERE MORE ACTIVE FIRES
ARE LOCATED.
AN UNSTABLE AND FAIRLY MOIST AIRMASS WILL HANG OVER MUCH OF
ALBERTA, WITH THE MOST MOISTURE AND HUMIDITY OVER THE PEACE
AND GRANDE PRAIRIE REGION WHERE NEARLY 2000 J/KG OF MLCAPE CREATED
FROM DEWPOINTS IN THE MID TEENS. IN THIS NORTHWESTERN
CORNER OF ALBERTA, SHEAR IS BETTER ALIGNED TO CREATE MULTICELL
STORMS THAT COULD BRING WIND, RAIN OR HAIL HAZARDS TO THIS AREA.
ANOTHER AREA OF MODERATE INSTABLITY AND SHEAR WILL BE ON THE OTHER
SIDE OF THE DIFFLUENT FLOW OVER SOUTHERN ALBERTA. LESS IMPRESSIVE
THAN IN THE NORTH, WIND AND PERHAPS HAIL ARE THE PRIMARY THREATS HERE
IN MULTICELLS.
NEARER THE UPPER RIDGE OVER THE NORTHERN PRAIRIES, HEAT WARNINGS
REMAIN IN EFFECT.
NWT...SMOKE CONTINUES TO DRIFT IN THE AREA BOTH FROM LOCAL FIRES
WHICH HAVE PROMPTED EVACUATION NOTICES AND FROM FIRES BACK IN
SASKATCHEWAN. AIR QUALITY RISK IS GENERALLY SITTING AROUND MODERATE
IN THE REGION FOR NOW BUT IT REMAINS TOO EARLY TO END THE AIR QUALITY
WARNING HERE.
THE SEVERE THREAT MENTIONED PREVIOUSLY OVER NORTHWESTERN ALBERTA WILL
BE POKING INTO THE NWT. SHEAR WILL BE STRONG ENOUGH TO SUSTAIN
MULTICELLS HERE, AND THERE'S SOME CHANCE OF HAZARDOUS WEATHER BETWEEN
FORT PROVIDENCE AND FORT SIMPSON.
HEAT WARNINGS AROUND GREAT SLAVE LAKE WILL CONTINUE UNTIL THURSDAY OR
FRIDAY WITH THE INFLUENCE OF THE UPPER RIDGE EAST OF THAT AREA.
SK/MB...A MUCH QUIETER DAY -- FINALLY -- FOR CONVECTION OVER THE
EASTERN PRAIRIES TODAY AS A A GENERALLY UNSTABLE BUT MUCH LESS
ENERGETIC AIR MASS MOVES ACROSS THE REGION. SCATTERED THUNDERSTORMS
AND SHOWERS WILL BE POSSIBLE ACROSS SOUTHERN SASKATCHEWAN AND PARTS
OF SOUTHERN MANITOBA TODAY, BUT WITH MLCAPE VALUES OF A FEW HUNDRED
J/KG OR LESS, NO SIGNIFICANT ORGANIZED SEVERE THREAT EXISTS. WITH A
RELATIVELY STRONG FLOW REGIME ACROSS THE REGION, THOUGH, A FEW STRONG
TO MARGINALLY SEVERE WIND GUSTS POSSIBLE IN PASSING SHOWERS OR
THUNDERSTORMS.
THE THUNDERSTORM RISK WILL SHIFT MAINLY TO SOUTHWEST SASKATCHEWAN ON
WEDNESDAY WHERE AROUND 500 J/KG OF MLCAPE WILL COMBINE WITH 15 TO 20
KNOTS OF BULK SHEAR. LIMITED SEVERE RISK, BUT AN ISOLATED STORM
CAPABLE OF LARGE HAIL OR DAMAGING WINDS COULD BE POSSIBLE. FURTHER
EAST, SHOWERS AND ISOLATED THUNDERSHOWERS WILL DROP THROUGH SOUTHERN
MANITOBA THROUGH THE DAY. THERE WILL ALSO BE A RISK OF FUNNEL CLOUDS
MOSTLY OVER CENTRAL MANITOBA IN THE VICINITY OF THE UPPER LOW.
WRAP-AROUND PRECIPITATION WILL GRADUALLY TAPER OFF OVER EASTERN
SASKATCHEWAN AND WESTERN MANITOBA TODAY. RAINFALL TOTALS HAVE BEEN
SIGNIFICANT ACROSS THE REGION WITH 40 TO 70 MM IN THE MINNESOTA AND
STE. ROSE REGIONS, WHILE AMOUNTS INCREASE SUBSTANTIALLY HEADING INTO
THE DAUPHIN AND KAMSACK AREAS. RAINFALL OF 100 TO 175 MM HAS BEEN
WIDESPREAD ACROSS THE AREA WITH THE HIGHEST AMOUNTS OVER A 24 HOUR
PERIOD REPORTED AT SASKATCHEWAN WFM STATION DUCKM WHICH HAS RECEIVED
165 MM OF RAIN. THROUGHOUT THE DAUPHIN REGION, ALL GAUGE READINGS FOR
24-HOUR RAINFALL HAVE EXCEEDED 100 MM WITH DAUPHIN REPORTING 108 MM
AND MANITOBA AGRICULTURE STATIONS REPORTING UP TO 135 MM AS OF
WRITING.
FURTHER NORTH, THESE INTENSE ACCUMULATIONS EASE INTO THE SWAN RIVER
REGION WITH GENERAL ACCUMULATIONS DROPPING BACK INTO THE 50 TO 70 MM
RANGE.
THE ORGANIZED RAIN WILL COME TO AN END THIS EVENING, LEAVING BEHIND
SHOWERS THAT PERSIST FOR ANOTHER DAY OR TWO.
MODERATE TO STRONG SOUTHWESTERLY WINDS HAVE DEVELOPED ALONG THE
SOUTHERN FLANK OF THE MANITOBA LOW WITH WIND GUSTS OF 60 TO 80 KM/H
LIKELY THROUGH THE AFTERNOON HOURS. THE WINDS WILL EASE THIS EVENING.
THE THUNDERSTORM RISK WILL SHIFT MAINLY TO SOUTHWEST SASKATCHEWAN ON
WEDNESDAY WHERE AROUND 500 J/KG OF MLCAPE WILL COMBINE WITH 15 TO 20
KNOTS OF BULK SHEAR. LIMITED SEVERE RISK, BUT AN ISOLATED STORM
CAPABLE OF LARGE HAIL OR DAMAGING WINDS COULD BE POSSIBLE. FURTHER
EAST, SHOWERS AND ISOLATED THUNDERSHOWERS WILL DROP THROUGH SOUTHERN
MANITOBA THROUGH THE DAY.
IN NORTHERN MANITOBA, WILDFIRE SMOKE WILL CONTINUE TO PROPAGATE
THROUGH MUCH OF THE REGION, GRADUALLY SHIFTING TO BE A CONCERN FOR A
COUPLE AREAS ALONG THE SASKATCHEWAN BORDER AS AN EASTERLY FLOW
DEVELOPS -- MAINLY PARTS OF THE THOMPSON, LYNN LAKE, AND FLIN FLON
REGIONS.
NUNAVUT...ABOVE NORMAL TEMPERATURES CONTINUE THIS WEEK ACROSS MUCH OF
THE EASTERN ARCTIC. NO HEAT WARNINGS ARE REQUIRED AT THIS TIME, BUT A
BUILDING LOW PRESSURE SYSTEM MAY REQUIRE HEAT WARNINGS BY THE END OF
THE WEEK.
A FEW SCATTERED SHOWERS WILL FALL OVER SOUTHERN BAFFIN ISLAND AS A
LOW PRESSURE SYSTEM REMAINS OVER THE AREA FOR THE NEXT 12 TO 24
HOURS.
FINALLY, A LOW PRESSURE SYSTEM PASSING THROUGH THE HIGH ARCTIC MAY
GIVE GUSTY WINDS TO ARCTIC BAY AND POND INLET LATE WEDNESDAY INTO
WEDNESDAY NIGHT.
END/VROLIJK/ALBERS
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page