591
FNUS73 KMPX 101147
FWSMPX

Spot Forecast for Lake Johanna Ice Shelf Sumac...The Nature Conservancy
National Weather Service Twin Cities/Chanhassen MN
647 AM CDT Wed Sep 10 2025

Forecast is based on ignition time of 1100 CDT on September 10.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.

Please contact our office if you have questions or concerns with
this forecast.

.DISCUSSION...
For the Lake Johanna Ice Shelf Sumac prescribed fire, dense Fog
will continue to mix out and become mostly clear by mid morning.
No rain is in the forecast today. Easterly winds between 5-7kts
with occasional gusts up to 12kts can be expected. Relative
humidity values will continue to decrease as fog diminishes and
reaching the low 60 percents by noon.

.REST OF TODAY...

Sky/weather.........Partly sunny (45-55 percent) then becoming
                    sunny (10-20 percent).
Temperature.........64 at ignition...Max 73.
RH..................87 percent at ignition...Min 62 percent.
Wind (20 ft)........Winds east at 6 mph at ignition...otherwise
                    East winds 6 to 7 mph.
Smoke dispersal.....Fair /14400 knot-ft/ at ignition. Max...fair
                    /25100 knot-ft/.
Mixing height.......1600 ft AGL at ignition...otherwise 3000 ft
                    AGL.
Transport winds.....East 9 to 10 mph.

TIME (CDT)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky cover.......MC  MC  PC  MCR MCR MCR MCR MCR CLR CLR CLR MCR
Weather cov.....
Weather type....
Tstm cov........
Temp............64  67  69  71  73  73  73  72  68  64  61  59
RH..............87  78  73  68  64  62  64  64  76  87  93  96
20 FT wind dir..E   E   E   E   E   E   E   E   E   E   E   E
20 FT wind spd..6   6   7   7   7   7   6   6   6   5   6   6
20 FT wind gust.10  12  13  12  13  12  12  12  9   8   9   9
Mix hgt (kft)...1.6 2.1 2.2 2.5 2.8 3.0 2.9 2.2 0.4 0.3 0.3 0.3
Transp wind dir.E   E   E   E   E   E   E   E   E   E   E   E
Transp wind spd.10  10  10  10  10  9   9   10  8   8   9   9

.TONIGHT...

Sky/weather.........Mostly clear (15-25 percent). Patchy fog early
                    in the morning.
Temperature.........Min 55.
RH..................Max 100 percent.
Wind (20 ft)........East winds 5 to 6 mph.
Smoke dispersal.....Fair (19400 knot-ft) early in the evening
                    decreasing to poor (2200 knot-ft) late in the
                    night.
Mixing height.......300 ft AGL.
Transport winds.....East 8 to 12 mph.

.THURSDAY...

Sky/weather.........Mostly sunny (45-55 percent). Patchy fog early
                    in the morning.
Temperature.........Max 75.
RH..................Min 62 percent.
Wind (20 ft)........Southeast winds 6 to 13 mph.
Smoke dispersal.....Poor (3500 knot-ft) early in the morning
                    increasing to fair (28400 knot-ft) in the
                    afternoon.
Mixing height.......2400 ft AGL.
Transport winds.....Southeast 10 to 14 mph.

$$
Forecaster...Dunleavy
Requested by...Ben Carlson
Type of request...PRESCRIBED
.TAG 2521687.0/MPX
.DELDT 09/10/25
.FormatterVersion 2.0.0
.EMAIL benjamin.carlson@tnc.org