987
FXUS63 KGRR 122307
AFDGRR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
707 PM EDT FRI JUN 12 2026
KEY MESSAGES
- DRY WEATHER CONTINUES THROUGH THE FIRST HALF OF TOMORROW
- SHOWERS AND STORMS POSSIBLE LATE SATURDAY WITH FOLD FRONT
- COOLER AND DRIER WEATHER THROUGH EARLY NEXT WEEK
DISCUSSION
ISSUED AT 240 PM EDT FRI JUN 12 2026
- DRY WEATHER CONTINUES THROUGH THE FIRST HALF OF TOMORROW
THE REPRIEVE FROM ANY SHOWERS AND STORMS WILL BE SHORT LIVED.
A LARGE UPPER LEVEL LOW WILL CONTINUES IS TREK THROUGH CENTRAL
WAY THROUGH CANADA TOMORROW. A SHORT WAVE TROUGH AND A
CORRESPONDING LOW WILL MOVE ALONG THE SOUTHERN GRADIENT OF THAT
SYSTEM. MODELS ARE IN FAIR AGREEMENT ON THE TRACK OF THIS SYSTEM.
NEAR NORMAL TEMPERATURES WILL CONTINUE WITH FAIR WEATHER TONIGHT
AND THROUGH MOST OF SATURDAY.
- SHOWERS AND STORMS POSSIBLE LATE SATURDAY WITH FOLD FRONT
THE ABOVE MENTIONED UPPER LEVEL LOW WILL SWEEP A COLD FRONT
THROUGH THE REGION SATURDAY EVENING. LATEST TIMING CONTINUES TO
DELAY FRONTAL PASSAGE. FIRST ROUND OF CAMS HAS CONVECTION REACHING
THE SHORES OF MICHIGAN TOMORROW EVENING. THE BEST MOISTURE ARE
INSTABILITY REMAINS IN THE GREAT PLAINS, HOWEVER THERE IS A MID
LEVEL SHORT WAVE WITH A WEAK LOW LEVEL JET THAT COULD AID IN STORM
DEVELOPMENT ALONG THE FRONTAL BOUNDARY. WITH THE DAYTIME
TEMPS 5 TO 10 DEGREES ABOVE NORMAL, IN THE 80S, AND DEWPOINTS IN
THE 60S THE AIRMASS WILL AID CONVECTION DEVELOPMENT. DUE TO THOSE
CONSIDERATIONS, SPC HAS INCLUDED MUCH OF LOWER MICHIGAN IN A
MARGINAL RISK TOMORROW EVENING. THIS SYSTEM SO FAR LOOKS WEAKER
AND DOES NOT CONTAIN THE FORCING AS LAST NIGHT'S. LATEST MODELS
ACTUALLY HAS THE WAVE ELONGATE AS IT MOVES EASTWARD AND DEEPEN AS
IT ADVECTS INTO THE MID ATLANTIC. SO EXPECT ANOTHER ROUND OF
SHOWERS AND STORMS TOMORROW EVENING, ESPECIALLY ALONG THE I 94
CORRIDOR.
- COOLER AND DRIER WEATHER THROUGH FIRST HALF OF THE WEEK
DOWNSLOPING FLOW IN THE WAKE OF THE COLD FRONT WILL BRING 850
TEMPS OF +4C OVERHEAD SUNDAY. THIS WILL DROP HIGHS 5 TO 10 DEGREES
BELOW NORMAL. SO A RETURN OF COOL SPRING GREETS US THIS WEEK AS
WE STAND ON THE EDGE OF SUMMER. THE WEEK AHEAD SHOULD HAVE
DAYTIME HIGHS IN THE 70S WITH LOWS IN THE 50S WHICH IS AROUND 5
DEGREES BELOW NORMAL. NEXT CHANCE FOR RAIN IS MIDWEEK FROM
SHORTWAVE THAT SHOULD CLIP THE GREAT LAKES.
AVIATION /00Z TAFS THROUGH 00Z SUNDAY/
ISSUED AT 650 PM EDT FRI JUN 12 2026
VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD. GUSTY WINDS
WILL SLACKEN OVERNIGHT AS THE INVERSION ENVELOPS THE REGION. THIS
INVERSION WILL BREAK DOWN WITH MORE GUSTY WINDS BY 17Z ON
SATURDAY. THE NEXT CONCERN FOR REDUCING CIGS AND VSBYS WILL BE
SATURDAY EVENING AROUND 00Z SUNDAY.
MARINE
ISSUED AT 240 PM EDT FRI JUN 12 2026
WAVES CONTINUE TO CALM THIS EVENING. THIS WILL BE SHORT LIVED AND
THE APPROACHING FRONT WILL BRING STRONG SOUTHWESTERLY FLOW THAT
WILL INCREASE WINDS AND WAVES EARLY SATURDAY. DUE TO THIS STRONG
SOUTHWESTERLY FLOW,
GRR WATCHES/WARNINGS/ADVISORIES
MI...BEACH HAZARDS STATEMENT FROM 5 AM EDT SATURDAY THROUGH LATE
SATURDAY NIGHT FOR MIZ037-043-050.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM SATURDAY TO 2 AM EDT SUNDAY FOR
LMZ847>849.
DISCUSSION...CERU
AVIATION...CERU
MARINE...CERU
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page