868
FNUS73 KGRR 211537
FWSGRR
SPOT FORECAST FOR BU 12...MI ARMY NATIONAL GUARD
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
ISSUED BY NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1137 AM EDT THU MAY 21 2026
FORECAST IS BASED ON IGNITION TIME OF 1200 EDT ON MAY 21.
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER
SERVICE.
PLEASE CONTACT OUR OFFICE AT (616) 949-5150, IF YOU HAVE QUESTIONS
OR CONCERNS WITH THIS FORECAST.
DISCUSSION
HIGH PRESSURE CENTERED ON THE NORTHERN GREAT LAKES WILL SUPPLY A
DRY NORTHEAST FLOW TODAY THROUGH FRIDAY. THIS WILL PLACE THE
WARMEST AND DRIEST CONDITIONS ALONG THE LAKE MICHIGAN SHORELINE.
LOW PRESSURE WILL MOVE TOWARD THE AREA FRIDAY NIGHT AND EARLY
SATURDAY. THIS WILL PROVIDE A FAIRLY WIDESPREAD AREA OF RAIN. THIS
MOVES OUT SATURDAY AFTERNOON, WITH A FEW SHOWERS AND A STORM
POSSIBLE SUNDAY.
REST OF TODAY
SKY/WEATHER.........MOSTLY SUNNY (35-45 PERCENT).
TEMPERATURE.........58 AT IGNITION...MAX 66.
RH..................44 PERCENT AT IGNITION...MIN 39 PERCENT.
WIND (20 FT)........WINDS NORTHEAST AT 9 MPH AT
IGNITION...OTHERWISE EAST WINDS 9 TO 10 MPH.
MIXING HEIGHT.......3400 FT AGL AT IGNITION...OTHERWISE 5000 FT
AGL.
MIXING WINDS........EAST 15 TO 17 MPH.
SMOKE DISPERSAL.....540 /GOOD/ AT IGNITION. MAX...810 /EXCELLENT/.
TIME (EDT) 12P 1PM 2PM 3PM 4PM 5PM 6PM 7PM 8PM 9PM 10P 11P
SKY (%).........38 39 41 40 39 37 36 35 34 36 39 41
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
TEMP............58 60 62 63 64 64 64 65 63 59 56 54
RH..............44 42 41 39 40 41 41 40 43 49 53 57
20 FT WIND DIR..NE E E E E E E E E E E E
20 FT WIND SPD..9 9 9 9 10 10 10 10 9 8 8 8
20 FT WIND GUST.18 18 18 20 20 20 21 21 20 18 18 18
MIX HGT (KFT)...3.4 3.8 4.3 4.6 4.9 5.0 4.9 4.7 1.6 0.7 0.7 0.6
MIXING WIND DIR.E E E E E E E E E E E E
MIXING WIND SPD.16 16 17 16 15 16 17 17 16 15 15 16
SMOKE DISPRSL...540 610 740 740 740 810 850 800 260 110 100 100
TONIGHT
SKY/WEATHER.........PARTLY CLOUDY (35-45 PERCENT) THEN BECOMING
MOSTLY CLOUDY (50-60 PERCENT).
TEMPERATURE.........MIN 45.
RH..................MAX 63 PERCENT.
WIND (20 FT)........EAST WINDS 7 TO 10 MPH. GUSTS UP TO 21 MPH
EARLY IN THE EVENING.
MIXING HEIGHT.......600 FT AGL.
MIXING WINDS........EAST 14 TO 17 MPH.
SMOKE DISPERSAL.....850 (EXCELLENT) EARLY IN THE EVENING DECREASING
TO 80 (POOR) LATE IN THE NIGHT.
FRIDAY
SKY/WEATHER.........PARTLY SUNNY (50-60 PERCENT).
TEMPERATURE.........MAX 69.
RH..................MIN 47 PERCENT.
WIND (20 FT)........EAST WINDS 8 TO 14 MPH. GUSTS UP TO 20 MPH
EARLY IN THE MORNING THEN 28 MPH IN THE LATE
MORNING AND AFTERNOON.
MIXING HEIGHT.......3500 FT AGL.
MIXING WINDS........EAST 14 TO 23 MPH.
SMOKE DISPERSAL.....90 (POOR) EARLY IN THE MORNING INCREASING TO
800 (EXCELLENT) IN THE AFTERNOON.
FORECASTER... BT
REQUESTED BY...MICHELE RICHARDS
TYPE OF REQUEST...PRESCRIBED
.TAG 2614224.0/GRR
.DELDT 05/21/26
.FORMATTERVERSION 2.0.0
.EMAIL RICHARDSM2@MICHIGAN.GOV,RKOZIATEK@NATURECENTER.ORG
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