Spot Forecast
Issued by NWS Omaha/Valley, NE
Issued by NWS Omaha/Valley, NE
845
FNUS73 KOAX 091404
FWSOAX
Spot Forecast for St. Marys Island...Iowa DNR
National Weather Service Omaha/Valley NE
904 AM CDT Thu May 9 2024
Forecast is based on ignition time of 1100 CDT on May 09.
If conditions become unrepresentative, contact the National Weather
Service.
.DISCUSSION...
Skies will become mostly cloudy by late morning into this
afternoon with an increasing chance for a few light showers and
perhaps an isolated thunderstorm. Rainfall amounts will be less
than 0.05". High temperatures will be in the mid to upper 60s
with lowest relative humidities of around 55 percent. North-
northwest winds of around 10 mph as of 8 AM will increase to 15
mph with gusts of 25 mph by late morning into this afternoon. The
winds will diminish to less than 10 mph by 8 PM.
Strongest Possible Wind Speeds on Day of Burn: sustained: 15-18
mph, gusts: 25-27 mph
Lowest Possible Relative Humidity on Day of Burn: 50-55 percent
.REST OF TODAY...
Sky/weather.........Partly sunny (55-65 percent). Slight chance of
showers late in the morning, then chance of
showers in the afternoon. Slight chance of
thunderstorms in the afternoon.
Max temperature.....Around 68.
Min humidity........55 percent.
Eye level winds.....North winds 8 to 10 mph.
Surface winds (mph).North winds 14 to 16 mph.
Wind (20 ft)........North winds 12 to 14 mph. Gusty and erratic
winds expected near thunderstorms in the
afternoon.
Mixing height.......4600 ft AGL.
Transport winds.....North 18 to 21 mph.
Smoke dispersal.....Good (59600 knot-ft) early in the morning
increasing to excellent (83600 knot-ft) in the
afternoon.
GFDI................0.
Haines Index........3 or very low potential for large plume
dominated fire growth.
TIME (CDT) 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........61 59 59 68 68 68 53
Weather cov.....SCH CHC CHC CHC CHC CHC CHC
Weather type....RW RW RW RW RW RW RW
Tstm cov........ SCH SCH SCH SCH SCH
Temp............62 65 65 66 67 67 67
RH..............71 64 62 62 58 58 58
20 FT wind dir..NW NW N N N N N
20 FT wind spd..11 12 12 13 13 12 11
20 FT wind gust.14 14 14 14 14 16 14
Eye lvl wnd dir.NW NW N N N N N
Eye lvl wnd spd.8 9 9 10 10 9 8
Eye lvl wnd gst.10 10 11 11 11 12 11
Surface wnd dir.NW NW N N N N N
Surface wnd spd.14 15 15 16 16 15 14
Surface wnd gst.17 17 18 18 18 20 18
Mix hgt (kft)...3.5 4.1 4.6 4.6 4.5 4.2 4.2
Transp wind dir.N NW NW N N N N
Transp wind spd.20 21 21 20 20 18 20
GFDI............0 0 0 0 0 0 0
Haines index....3 3 3 3 3 3 3
SDspl kt-ft/100060 74 84 83 76 67 61
.TONIGHT...
Sky/weather.........Mostly cloudy (45-55 percent) then becoming
partly cloudy (45-55 percent) then becoming
mostly cloudy (50-60 percent) then becoming
mostly clear (15-25 percent). Chance of rain
showers and slight chance of thunderstorms in
the evening, then chance of sprinkles
overnight.
Min temperature.....Around 47.
Max humidity........96 percent.
Eye level winds.....North winds up to 8 mph in the evening becoming
light.
Surface winds (mph).North winds 6 to 14 mph in the evening becoming
light.
Wind (20 ft)........North winds 5 to 12 mph in the evening becoming
light. Gusty and erratic winds expected near
thunderstorms early in the evening.
Mixing height.......400 ft AGL.
Transport winds.....North 13 to 20 mph decreasing to 7 to 10 mph in
the late evening and overnight.
Smoke dispersal.....Good (53700 knot-ft) early in the evening
decreasing to poor (400 knot-ft) late in the
night.
GFDI................0.
Haines Index........3 to 4 or very low to low potential for large
plume dominated fire growth.
TIME (CDT) 6 PM 8 PM 10 PM MIDNGT 2 AM 4 AM
Sky (%).........51 54 17 10 7 21
Weather cov.....CHANCE S CHC S CHC CHANCE
Weather type....RNSHWR RNSHWR RNSHWR RNSHWR NONE NONE
Tstm cov........S CHC S CHC
Temp............68 64 58 55 52 48
RH..............55 60 74 82 91 95
20 ft wind......N 11 N 8 N 6 N 5 N 4 NW 4
20 ft wind gust.14 11 8 6 5 6
Eye level wind..N 8 N 6 N 4 N 4 N 3 NW 3
Eye lvl wnd gst.11 8 6 5 4 4
Surface wind....N 14 N 10 N 8 N 6 N 5 NW 5
Surface wnd gst.18 14 10 8 6 7
Mix hgt (ft)....3900 1000 400 400 400 400
Transport wind..N 20 N 15 N 10 N 8 N 8 NW 7
GFDI............0 0 0 0 0 0
Haines index....3 4 4 4 4 4
SDspl kt-ft/100054 30 4 1 3 3
.FRIDAY...
Sky/weather.........Mostly sunny (35-45 percent).
Max temperature.....Around 75.
Min humidity........36 percent.
Eye level winds.....Light winds becoming northwest up to 9 mph
early in the morning.
Surface winds (mph).Northwest winds 6 to 15 mph.
Wind (20 ft)........Northwest winds 5 to 13 mph.
Mixing height.......7300 ft AGL.
Transport winds.....Northwest 7 to 15 mph increasing to 17 to 21
mph in the afternoon.
Smoke dispersal.....Poor (700 knot-ft) early in the morning
increasing to excellent (93300 knot-ft) in the
afternoon increasing to excellent (103100
knot-ft) in the afternoon.
GFDI................0.
Haines Index........4 or low potential for large plume dominated
fire growth.
TIME (CDT) 6 AM 8 AM 10 AM NOON 2 PM 4 PM
Sky (%).........28 22 16 41 62 68
Weather cov.....
Weather type....NONE NONE NONE NONE NONE NONE
Tstm cov........
Temp............47 51 63 70 74 75
RH..............95 92 62 43 37 37
20 ft wind......NW 4 W 5 W 7 NW 9 NW 11 NW 12
20 ft wind gust.5 6 10 13 16 17
Eye level wind..NW 3 W 4 W 5 NW 7 NW 8 NW 9
Eye lvl wnd gst.4 5 7 10 12 13
Surface wind....NW 5 W 6 W 9 NW 11 NW 14 NW 15
Surface wnd gst.6 8 12 16 20 21
Mix hgt (ft)....400 700 2200 5900 7200 6900
Transport wind..NW 7 NW 8 NW 12 N 17 NW 20 NW 21
GFDI............0 0 0 0 0 0
Haines index....4 4 4 4 4 4
SDspl kt-ft/10001 3 22 93 136 125
$$
Forecaster...Mead
Requested by...Matt Dollison
Type of request...PRESCRIBED
.TAG 2413607.0/OAX
.DELDT 05/09/24
.FormatterVersion 2.0.0
.EMAIL matt.dollison@dnr.iowa.gov