Alert archive / Montana / Lake Wind Advisories in 2021

Lake Wind Advisory 2, NWS Missoula, MT

April 11, 2021Flathead County, Lake County, Sanders County, Montana

NWS Missoula, MT issued this lake wind advisory at Apr 11, 2021, 1:25 PM MDT for Flathead County, Lake County, Sanders County, Montana. It took effect at Apr 12, 2021, 2:00 PM MDT. It was in force for 31 hr.

The area

The counties it named.

The facts

Issued
Apr 11, 2021, 1:25 PM MDT (19:25 UTC)
In effect from
Apr 12, 2021, 2:00 PM MDT
Expired
Apr 13, 2021, 9:00 PM MDT
In force
31 hr
Issued by
NWS Missoula, MT

Counties Flathead County, MT, Lake County, MT, Sanders County, MT

The radar

The Missoula radar (KMSX), 98 km from the middle of the area, began a volume at 19:24 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Spokane, WA (KOTX), launched 12:00Z, 7.4 hours before the alert went out and 149 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Spokane, WA at 12:00Z on 2021-04-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Spokane, WA at 12:00Z on 2021-04-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2148 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
-18 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

700 
WWUS75 KMSO 111925
NPWMSO

URGENT - WEATHER MESSAGE
National Weather Service Missoula MT
125 PM MDT Sun Apr 11 2021

MTZ003-121930-
/O.NEW.KMSO.LW.Y.0002.210412T2000Z-210414T0300Z/
Flathead/Mission Valleys-
125 PM MDT Sun Apr 11 2021

...LAKE WIND ADVISORY IN EFFECT FROM 2 PM MONDAY TO 9 PM MDT
TUESDAY...

* WHAT...Waves 1 to 3 feet with northeast winds 15 to 25 mph 
  with gusts up to 35 mph expected.

* WHERE...Flathead Lake, Flathead Valley, Mission Valley, and 
  Polson.

* WHEN...From 2 PM Monday to 9 PM MDT Tuesday.

* IMPACTS...Strong winds and rough waves will create hazardous 
  conditions for small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Boaters on area lakes should use extra caution since strong winds
and rough waves can overturn small craft.

&&

$$
1 follow-up statement
524 
WWUS75 KMSO 140318
NPWMSO

URGENT - WEATHER MESSAGE
National Weather Service Missoula MT
918 PM MDT Tue Apr 13 2021

MTZ003-140430-
/O.EXP.KMSO.LW.Y.0002.000000T0000Z-210414T0300Z/
Flathead/Mission Valleys-
918 PM MDT Tue Apr 13 2021

...LAKE WIND ADVISORY HAS EXPIRED...

Gusty winds will continue tomorrow, but gusts are expected to
remain below 30 mph with predominant winds below 20 mph.
Conditions will still be windy on Flathead Lake though.

$$

The office that day

Everything else NWS Missoula, MT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 10, 9:08 PM MDTSpecial Weather StatementMSOPowell37 min

Nearby

Lake Wind Advisories in Montana, 2021Every lake wind advisory in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.