574
FNUS73 KGRR 221556
FWSGRR

Spot Forecast for Dune and Swale...MIDNR
National Weather Service Grand Rapids MI
1156 AM EDT Wed May 22 2024

Forecast is based on ignition time of 1100 EDT on May 23.
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...
Dy weather on Thursday will be followed by increasing chances for
rain on Friday, with showers and thunderstorms expected by late
Friday morning into the afternoon.

.THURSDAY...

Sky/weather.........Sunny (5-15 percent).
Temperature.........71 at ignition...Max 77.
RH..................49 percent at ignition...Min 36 percent.
Wind (20 ft)........Winds southwest at 7 mph at
                    ignition...otherwise West winds 5 to 8 mph
                    decreasing to around 5 mph in the evening.
Mixing height.......3900 ft AGL at ignition...otherwise 5900 ft
                    AGL.
Mixing winds........Southwest 6 to 13 mph.
Smoke dispersal.....450 /good/ at ignition. Max...730 /excellent/.
Haines Index........5 or moderate potential for large plume
                    dominated fire growth at ignition...max 5.

TIME (EDT)      11 AM  1 PM   3 PM   5 PM   7 PM   9 PM
Sky (%).........20     13     7      1      2      6
Weather cov.....
Weather type....NONE   NONE   NONE   NONE   NONE   NONE
Tstm cov........
Temp............71     73     76     76     75     69
RH..............49     43     36     36     40     51
20 ft wind......SW 7   W 8    W 8    W 7    W 5    SW 2
20 ft wind gust.12     13     13     12     8      5
Mix hgt (ft)....3900   5700   5900   4900   1800   100
Mixing wind.....SW 12  SW 13  SW 12  W 9    W 6    SW 5
Haines index....5      5      5      5      5      5
Smoke disprsl...450    730    700    450    100    0

.THURSDAY NIGHT...

Sky/weather.........Mostly clear (5-15 percent).
Temperature.........Min 55.
RH..................Max 72 percent.
Wind (20 ft)........Light winds.
Mixing height.......100 ft AGL.
Mixing winds........Southwest around 5 mph shifting to the south.
Smoke dispersal.....0 (poor).
Haines Index........5 or moderate potential for large plume
                    dominated fire growth.

.FRIDAY...

Sky/weather.........Mostly sunny (35-45 percent). Chance of showers
                    in the afternoon. Slight chance of
                    thunderstorms late in the day.
Temperature.........Max 83.
RH..................Min 41 percent.
Wind (20 ft)........Light winds becoming south 5 to 7 mph. Gusty
                    and erratic winds expected near thunderstorms
                    late in the day.
Mixing height.......5700 ft AGL.
Mixing winds........South 9 to 17 mph increasing to 13 to 20 mph
                    late in the day.
Smoke dispersal.....40 (poor) early in the morning increasing to
                    1060 (excellent) in the afternoon.
Haines Index........4 or low potential for large plume dominated
                    fire growth.

$$
Forecaster...Ostuno
Requested by...Jeff Vasher
Type of request...PRESCRIBED
.TAG 2414912.0/GRR
.DELDT 05/22/24
.FormatterVersion 2.0.0
.EMAIL vasherj@michigan.gov