Rapid pressure rises and strong subsidence behind a cold front resulted in high winds across much of the Billings Forecast Area.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS BYZ wrote it up.
Rapid pressure rises and strong subsidence behind a cold front resulted in high winds across much of the Billings Forecast Area.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Billings, MT wrote its last area forecast discussion before the first event at May 6, 6:58 PM MST, 4 hours 3 minutes earlier.
Area Forecast Discussion...Updated
National Weather Service Billings MT
758 PM MDT Mon May 6 2024
.UPDATE...
Severe thunderstorm threat has ended this evening and all watches
have been cancelled. Will continue to see a few thunderstorms
mixed in with the more persistent rainfall over areas east of
Billings through the night and into tomorrow, in the vicinity of
the core of the upper low/cold pool aloft. Western edge of
precipitation is forecast to slowly shift eastward late this
evening into the early morning hours, moving out to around a
Musselshell to Hysham to Ashland line by 3am or so. This will end
precipitation for Billings, Sheridan and the Bighorn mountains for
the time being, and usher in stronger northwest winds late
tonight. Additional gusts in the 45 to 60 mph range are possible
in areas that have already seen strong gusts today, with higher
exposed locations the most likely to see a damaging wind gust or
two. Radar still showing returns over the Bighorn mountains, so
will leave the Winter Weather advisory in place for now, it
expires at midnight tonight which looks reasonable at this point.
No changes to the widespread High Wind Warnings across the
forecast area. PNS product was sent earlier this evening for
strong wind and precipitation reports. Chambers
&&
.DISCUSSION...
Tonight through Tuesday night...
Dynamic upper low currently over northeastern WY is affecting our
weather in several ways, with a severe thunderstorm threat over
Carter and Fallon Counties as low-level east/southeasterly winds
bring relatively warm, moist air and associated instability to
those areas, steady rain over central areas, snow in the Bighorn
Mountains, and strong gusty winds over western and central areas.
Ensemble means generally show 500 mb low meander over the western
Dakotas into Tuesday night, with more weather impacts for our
area. They also show 700 mb winds strengthening over our area late
this afternoon-evening then staying strong through Tuesday night.
At the surface, low pressure probably in the lower 980s mb will
also meander in the western Dakotas.
As we go through the rest of this afternoon, the surface boundary
in Carter/Fallon Counties should move northeastward and the area
of appreciable instability will depart the area. Thus, the severe
thunderstorm threat should diminish late this afternoon or early
evening. The Severe Thunderstorm Watch for Carter and Fallon
Counties is in effect until 7 PM MDT tonight. Main hazards from
the thunderstorms will be strong, damaging wind gusts and large
hail.
The surface pressure gradient between the surface low to our east
and higher surface pressure to our west plus strong 700 mb winds
over our area should support more strong, gusty winds over much of
the area tonight into Tuesday evening. Look for wind gusts to
50-60 mph through Tuesday night, so have extended the High Wind
Warning and expanded it in area to include much of the lower
elevations except for Fallon County. If you will be traveling with
a high profile vehicle during this time please use caution.
The low pressure system should also bring more precipitation to
the region. A band of rain forced by frontogenesis is gradually
sliding eastward, east of Billings, into southeast MT. Look for
much of the additional rainfall tonight into Tuesday morning to
occur in southeast MT, where large-scale ascent and frontogenesis
work constructively to produce precipitation. NBM shows a 30-65%
chance of at least 0.75 inches additional rain tonight from
roughly Rosebud/Treasure Counties eastward to the Dakota border.
Greatest probability is near Miles City. Then for Tuesday
afternoon a disturbance rotating around the upper low should bring
another round of rain into Tuesday night to much of the area
including Billings. The combination of rain and wind will make for
unfavorable conditions for travelers and anyone outdoors.
Snow in the Bighorn Mountains will continue into this evening
before diminishing. Additional snow accumulation there will be up
to 7 inches or so. Use caution if you will be heading to the high
country. Snow should return to the Bighorn Mountains Tuesday
afternoon into Tuesday night.
Low temperatures will generally be in the 30s and 40s tonight
then 30s Tuesday night. High temperatures on Tuesday will be in
the 40s and 50s. RMS
Wednesday through Monday...
Cool and unsettled weather to start the extended period, then dry
weather with a warming trend expected. On Wednesday, models were
not in good agreement with the position of the upper low that is
affecting the area during the short-term. Upper low was progged to
be E or SE of the forecast area depending on the model. Either
way, cyclonic flow will be over the region and a back-door cold
front moves SW through the eastern part of the area. PWAT's
are forecast to be around normal for this time of year with not
any notable instability. Highs will only be in the 40s and 50s.
With plenty of energy in the flow aloft, PoPs are high, near 100%
through the day. NBM probabilities of a half /0.50/ inch or more
of rainfall were 58% for KBIL and 39% for KSHR on Wednesday. And
the EFI had a high value of .8 for snow over areas NW and S of
KBIL (this includes Tue. night). So have a mix of rain and snow W
and S of KBIL mainly in the morning. Not expecting any low
elevation snow accumulation, but the mountains will have decent
accumulation with close to a foot in the highest elevations of the
Beartooths/Absarokas. In addition, winds will still be an issue
based on the ECMWF ensemble, and the EFI showing .8-.9 over the SW
half of the forecast area. Gusts into the 50s are not out of the
question for this area. For Thursday, upper ridge builds in from
the W and results in a high over low pressure situation. PoPs
remain moderately high, from 40-60% through Thursday. Low-
elevation rain with mountain snow will continue, with the
mountains picking up a few more inches of snow. Highs will be near
normal.
A high over low situation will continue through Saturday with
model differences. Other than some low PoPs over the NE Bighorns,
the area will be dry with highs climbing into the 70s. NW flow
will be over the area for Sunday and ridging or zonal flow will be
over the region on Monday. Next best precipitation chance is Mon.
afternoon with 20-40% chances of showers and thunderstorms. Arthur
&&
.AVIATION...
Strong wind gusts will continue tonight through Tuesday with NW
winds gusting from 45 to 55 kt, and lighter winds in the KBHK
area. From KBIL-KSHR W, expect MVFR to VFR conditions. E of this
line, there will be IFR/LIFR conditions due to rain and
thunderstorms. Severe thunderstorms, with wind gusts to 65 kt and
large hail, are possible over Fallon and Carter Counties through
this evening. Conditions will be from MVFR to LIFR over the entire
area Tue. afternoon. Expect localized to areas of mountain
obscuration through Tuesday. Arthur
&&
.PRELIMINARY POINT TEMP/POPS...
Tue Wed Thu Fri Sat Sun Mon
-----------------------------------------------------------
BIL 043/051 039/050 043/060 042/069 045/075 047/077 049/076
66/W 9+/W 97/T 11/U 01/U 11/U 13/T
LVM 037/049 036/046 038/057 037/065 040/071 043/073 045/074
05/W 9+/W 84/W 10/U 01/U 12/W 13/W
HDN 041/050 037/053 042/062 040/069 041/075 044/078 046/077
98/W ++/W 97/T 21/B 01/U 11/U 12/W
MLS 039/045 039/055 042/063 043/067 043/074 045/076 047/076
99/W 99/W 64/W 11/U 01/U 11/U 12/W
4BQ 037/045 037/051 041/060 043/066 041/072 045/076 047/075
+8/W 99/W 85/W 11/B 01/U 11/U 12/T
BHK 036/045 034/054 038/063 040/065 040/070 042/073 044/074
79/T 88/W 43/W 11/U 01/U 01/U 11/U
SHR 039/053 034/046 038/057 037/064 037/070 041/073 043/073
74/W 9+/W 97/T 21/B 01/U 12/T 13/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...High Wind Warning in effect until midnight MDT Tuesday night
FOR ZONES 29>32-57-173.
High Wind Warning now in effect until midnight MDT Tuesday
night FOR ZONES 34-42-138-170-235.
High Wind Warning in effect until 6 PM MDT Tuesday FOR ZONES
36-37-58.
High Wind Warning remains in effect until 6 AM MDT Wednesday
FOR ZONES 63-65-66-141-172-228.
WY...High Wind Warning now in effect until midnight MDT Tuesday
night FOR ZONE 199.
Winter Weather Advisory remains in effect until midnight MDT
tonight FOR ZONE 198.
&&
weather.gov/billingsPreliminary Local Storm Report
National Weather Service Billings, MT
746 PM MDT Mon May 06 2024
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0420 PM Non-Tstm Wnd Gst 10 E Molt 45.85N 108.73W
05/06/2024 M50.00 MPH Yellowstone MT Trained Spotter
0445 PM Non-Tstm Wnd Gst 9 NE Reed Point 45.80N 109.43W
05/06/2024 M55.00 MPH Stillwater MT Mesonet
0445 PM Non-Tstm Wnd Gst 2 W Reed Point 45.71N 109.58W
05/06/2024 M58.00 MPH Sweet Grass MT Dept of Highways
0445 PM Non-Tstm Wnd Gst 7 S Reedpoint 45.61N 109.56W
05/06/2024 M55.00 MPH Stillwater MT Mesonet
0500 PM Non-Tstm Wnd Gst 5 N Rapleje 46.04N 109.24W
05/06/2024 M53.00 MPH Stillwater MT Mesonet
0500 PM Non-Tstm Wnd Gst 1 WNW Ingomar 46.58N 107.40W
05/06/2024 M51.00 MPH Rosebud MT Dept of Highways
0500 PM Non-Tstm Wnd Gst 9 NE Reed Point 45.80N 109.43W
05/06/2024 M53.00 MPH Stillwater MT Mesonet
0500 PM Non-Tstm Wnd Gst 7 E Reedpoint 45.68N 109.40W
05/06/2024 M51.00 MPH Stillwater MT Mesonet
0500 PM Non-Tstm Wnd Gst 7 S Reedpoint 45.61N 109.56W
05/06/2024 M56.00 MPH Stillwater MT Mesonet
0515 PM Non-Tstm Wnd Gst 9 NE Reed Point 45.80N 109.43W
05/06/2024 M56.00 MPH Stillwater MT Mesonet
0515 PM Non-Tstm Wnd Gst 2 W Reed Point 45.71N 109.58W
05/06/2024 M59.00 MPH Sweet Grass MT Dept of Highways
0515 PM Non-Tstm Wnd Gst 2 SSW Big Timber 45.81N 109.98W
05/06/2024 M61.00 MPH Sweet Grass MT ASOS
0518 PM Non-Tstm Wnd Gst 9 E Lodge Grass 45.31N 107.17W
05/06/2024 M56.00 MPH Big Horn MT Mesonet
0530 PM Non-Tstm Wnd Gst 7 E Reedpoint 45.68N 109.40W
05/06/2024 M52.00 MPH Stillwater MT Mesonet
0530 PM Non-Tstm Wnd Gst 2 W Reed Point 45.71N 109.58W
05/06/2024 M58.00 MPH Sweet Grass MT Dept of Highways
0530 PM Non-Tstm Wnd Gst 2 W Reed Point 45.71N 109.58W
05/06/2024 M58.00 MPH Sweet Grass MT Dept of Highways
0535 PM Non-Tstm Wnd Gst 2 SSW Big Timber 45.81N 109.98W
05/06/2024 M60.00 MPH Sweet Grass MT ASOS
0555 PM Non-Tstm Wnd Gst 2 SSW Big Timber 45.81N 109.98W
05/06/2024 M56.00 MPH Sweet Grass MT ASOS
0600 PM Non-Tstm Wnd Gst 2 E Broadus 45.44N 105.36W
05/06/2024 M53.00 MPH Powder River MT Mesonet
0630 PM Non-Tstm Wnd Gst 2 E Broadus 45.44N 105.36W
05/06/2024 M62.00 MPH Powder River MT Mesonet
0635 PM Non-Tstm Wnd Gst 3 NW Billings 45.81N 108.55W
05/06/2024 M56.00 MPH Yellowstone MT ASOS
0645 PM Non-Tstm Wnd Gst 7 S Reedpoint 45.61N 109.56W
05/06/2024 M54.00 MPH Stillwater MT Mesonet
0655 PM Non-Tstm Wnd Gst 2 SSW Big Timber 45.81N 109.98W
05/06/2024 M59.00 MPH Sweet Grass MT ASOS
0700 PM Non-Tstm Wnd Gst 7 S Reedpoint 45.61N 109.56W
05/06/2024 M59.00 MPH Stillwater MT Mesonet
0712 PM Rain 5 NW Forsyth 46.34N 106.70W
05/06/2024 M1.37 inch Rosebud MT Trained Spotter
Moderate rain at 1 pm MDT.
&&
TSPreliminary Local Storm Report
National Weather Service Billings, MT
813 PM MDT Mon May 06 2024
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0715 PM Non-Tstm Wnd Gst 9 NE Reed Point 45.80N 109.43W
05/06/2024 M52.00 MPH Stillwater MT Mesonet
0718 PM Non-Tstm Wnd Gst 3 NW Billings 45.81N 108.55W
05/06/2024 M58.00 MPH Yellowstone MT ASOS
0718 PM Non-Tstm Wnd Gst 7 SSE Pryor 45.34N 108.49W
05/06/2024 M52.00 MPH Big Horn MT Mesonet
0718 PM Non-Tstm Wnd Gst 17 S Fort Smith 45.07N 107.89W
05/06/2024 M53.00 MPH Big Horn MT Mesonet
0724 PM Non-Tstm Wnd Gst 4 WSW Moorhead 45.06N 105.95W
05/06/2024 M52.00 MPH Powder River MT Mesonet
0730 PM Non-Tstm Wnd Gst 9 NE Reed Point 45.80N 109.43W
05/06/2024 M52.00 MPH Stillwater MT Mesonet
0750 PM Rain 20 ESE Colstrip 45.82N 106.23W
05/06/2024 M1.33 inch Rosebud MT Co-Op Observer
&&
trcThe national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
Winds gusted to 62 mph at the Sheridan Airport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2024Every state in 2024This day in weather historyWarnings in Wyoming, May 2024
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1173326.