A powerful frontal passage occurred during evening hours of the 6th into the early morning hours of the 7th. Winds gusting 50 to 65 mph were common across the central areas of the Billings Forecast Area.
Every event with a place to put it; 4 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.
A powerful frontal passage occurred during evening hours of the 6th into the early morning hours of the 7th. Winds gusting 50 to 65 mph were common across the central areas 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, 2:00 PM MST, 4 hours 50 minutes earlier.
Area Forecast Discussion
National Weather Service Billings MT
300 PM MDT Wed May 6 2020
.DISCUSSION...
Tonight through Thursday night...
THe upper low off the coast of the Pacific Northwest, and it's
associated cold front well east of on remain on track, still to
bring about high winds and rain and snow showers to the area this
evening and through tomorrow morning.
The surface low and cold front, currently located over the divide,
has been bringing about 3-hr pressure rises of up to 8 mb behind
it throughout the day, boosting confidence in winds increasing
with its passage and behind it, gusting up to 60 mph across much
of south-central MT and north-central WY. The front will pass
through Livingston between 4-6 PM MDT this evening, reaching
Billings between 6-7 PM MDT, and continue to move east through the
evening and overnight hours. Strongest winds will be with the
initial frontal passage, but moderate to high winds will persist
behind it. However, it's magnitude will depend on when the
inversion takes over, which some uncertainty still exists with. A
second surge of wind will occur Thursday morning when surface
temperatures increase and leftover strong winds aloft mix down
while the upper low wraps around. Strong winds will move out of
the area late Thursday morning and early afternoon.
The second part to this story is the precipitation. A moderately
strong squall line looks to set up alongside the cold front as it
passes through, bringing a shot of moderate rain showers to area
mainly north of Billings, with a slight chance for thunderstorms
as well. As the system wraps around tomorrow morning, more rain
and snow showers will pass over the lower elevations, though minor
accumulations are expected with this round.
Lastly, the mountains, especially higher elevations, could see 2-5
inches of snow overnight. After this system moves through,
unsettled weather with northerly flow aloft will persist into the
weekend. Highs for Thursday will only reach the low to mid 50s,
with lows reaching the low to mid 30s Thursday night.
Vertz
Friday through Wednesday...
Cool, unsettled northwest flow will continue over the area through
the weekend into early next week. Multiple disturbances dropping
through the region will allow for mountain snow and shower
chances, along with periods of gusty winds. Some weak instability
will promote isolated thunderstorms at times. Short-lived ridging
looks to build in over the area for Tuesday. There are
indications of a more significant system moving into the region
for the middle of the week.
High temperatures are forecast to range from the 60s on Friday, to
mainly the 50s through the weekend into next week. Lows should
mainly be in the 30s most nights/mornings, with some locations
dropping into the 20s. STP
&&
.AVIATION...
VFR conditions will prevail over much of the area through the rest
of the afternoon. A cold front pushing into western areas by 22z
will generate showers and isolated thunderstorms, causing
localized MVFR conditions. As the cold front moves out of the
mountains, expect a squall line to develop and shoot eastward
across the plains through the evening hours. Scattered showers and
wind gusts to 50kts can be expected with this squall. By midnight
the front will push into southeast Montana and winds will weaken
to gusts in the 35kt range. Precipitation will increase overnight,
especially north of a Harlowton to Broadus line where moderate
precipitation and MVFR conditions will prevail. Snow will develop
in the evening hours over area mountains and foothills behind the
cold front, with local IFR conditions and mountain obscuration.
Showers will continue on Thursday producing MVFR conditions.
Chambers/STP
&&
.PRELIMINARY POINT TEMP/POPS...
Thu Fri Sat Sun Mon Tue Wed
-----------------------------------------------------------
BIL 040/056 035/064 040/059 036/057 038/053 039/058 042/059
65/W 22/W 32/W 01/B 13/W 33/W 45/W
LVM 036/055 034/062 037/060 034/058 036/054 037/058 039/059
44/W 23/W 21/B 01/E 24/W 35/T 67/T
HDN 038/056 033/065 039/057 032/058 036/054 038/060 041/060
55/W 22/W 42/W 01/B 13/W 33/W 55/W
MLS 042/056 034/064 040/054 032/055 033/055 036/058 040/059
56/W 02/W 43/W 11/B 01/B 12/W 34/W
4BQ 038/053 031/062 037/053 030/054 033/052 036/056 039/061
44/W 21/B 33/W 11/B 12/W 22/W 34/T
BHK 039/053 030/062 036/049 029/050 028/052 031/053 035/057
67/W 01/B 44/W 12/W 11/B 11/E 33/W
SHR 035/052 030/062 036/055 030/056 034/054 036/059 039/062
36/W 22/W 42/W 11/B 23/W 32/T 44/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...High Wind Warning in effect from 6 PM this evening to noon
MDT Thursday FOR ZONES
29-30-42-56>58-138-139-170-172-173-228-235.
High Wind Warning in effect until noon MDT Thursday FOR ZONES
34-40-141.
Wind Advisory in effect until noon MDT Thursday FOR ZONES
65-66.
WY...High Wind Warning in effect from 6 PM this evening to noon
MDT Thursday FOR ZONE 199.
&&
weather.gov/billingsPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BILLINGS MT
706 PM MDT WED MAY 06 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0457 PM TSTM WND GST 2 W REED POINT 45.71N 109.58W
05/06/2020 M52.00 MPH SWEET GRASS MT DEPT OF HIGHWAYS
0655 PM TSTM WND GST 2 SSW BIG TIMBER 45.81N 109.98W
05/06/2020 M53.00 MPH SWEET GRASS MT AWOS
&&
RMSThe national radar mosaic for the moment the first event began.
4 high wind. Local standard time, as filed.
Winds gusted to 58 mph 6 miles east of Columbus.
Winds gusted 60 to 65 mph across the area.
A gust of 59 mph was recorded at the Kilo RAWS.
Winds gusted to 58 mph across the area.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2020Every state in 2020This day in weather historyWarnings in Montana, May 2020
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: 887159, 887131, 887133, 887134.