Alert archive / Idaho / Winter Storm Warnings in 2009

Winter Storm Warning 16, NWS Missoula, MT

April 1, 2009Clearwater County, Idaho

NWS Missoula, MT issued this winter storm warning at Apr 1, 2009, 8:58 PM PDT for Clearwater County, Idaho. It took effect at Apr 1, 2009, 11:00 PM PDT. It was in force for 22 hr. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Apr 1, 2009, 8:58 PM PDT (03:58 UTC)
In effect from
Apr 1, 2009, 11:00 PM PDT
Expired
Apr 2, 2009, 8:47 PM PDT
In force
22 hr
Issued by
NWS Missoula, MT

County Clearwater County, ID

The radar

The Missoula radar (KMSX), 133 km from the middle of the area, began a volume at 03:59 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.

What was reported inside it

TimeReportWhereRemark
Apr 2, 8:30 AM PDTHEAVY SNOW 85 Nnw Orofino, ID

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Spokane, WA (KOTX), launched 00:00Z, 4.0 hours before the alert went out and 127 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 00:00Z on 2009-04-02Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Spokane, WA at 00:00Z on 2009-04-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -16 square meters per square second.1939587897117Sfc1 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
691 m above ground
0-6 km bulk shear
85 kt
0-1 km storm-relative helicity
-16 m²/s²
0-3 km storm-relative helicity
141 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WWUS45 KMSO 020358
WSWMSO

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MISSOULA MT
958 PM MDT WED APR 1 2009

.THE ADVANCING PACIFIC STORM SYSTEM IS COMING IN MUCH FURTHER
SOUTH THAN PREVIOUSLY FORECAST. NORTH CENTRAL IDAHO IS NOW THE
AREA EXPECTED TO BE THE MOST IMPACTED BY THIS SYSTEM...WITH MUCH
LESSER AMOUNTS IN NORTHWEST MONTANA. WITH THE COOL LOW LEVELS FROM THE
CONVECTIVE SHOWERS EARLIER TODAY...THE PRECIPITATION CURRENTLY
MOVING IN IS FALLING AS SNOW. SNOW LEVELS WILL REMAIN NEARLY
STEADY OR FALL SLIGHTLY AFTER MIDNIGHT WITH THE PRECIPITATION
MOVING IN. THE BEST ACCUMULATING SNOW IS EXPECTED OVER THE CENTRAL
AND NORTHERN CLEARWATER MOUNTAINS INCLUDING LOLO PASS AND THE
HIGHER TERRAIN OF THE CAMAS PRAIRIE INCLUDING WHITEBIRD AND GREER
GRADES. WITH SNOW LEVELS RISING IN THE AFTERNOON...SNOW WILL
CONTINUE...BUT ACCUMULATIONS ARE EXPECTED TO DECREASE AS THERE IS
SETTLING AND OR MELTING AS IT FALLS...ESPECIALLY IN THE CAMAS
PRAIRIE REGION. WITH THE PASSAGE OF A SURFACE FRONT...INCREASED
WINDS IN THE AFTERNOON WILL PRODUCE AREAS OF BLOWING SNOW REDUCING
VISIBILITIES. LOCAL BLIZZARD CONDITIONS ARE POSSIBLE OVER
WHITEBIRD AND GREER GRADES IN THE AFTERNOON.

MTZ002-004-020500-
/O.CAN.KMSO.WW.Y.0049.090402T0600Z-090403T0600Z/
WEST GLACIER REGION-LOWER CLARK FORK REGION-
958 PM MDT WED APR 1 2009

...WINTER WEATHER ADVISORY IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS CANCELLED THE WINTER
WEATHER ADVISORY. 

HEAVIEST SNOW ACCUMULATIONS ARE EXPECTED SOUTH OF LOOKOUT AND MARIAS
PASSES. THEREFORE THE WINTER WEATHER ADVISORY HAS BEEN CANCELLED.

$$

IDZ005-021200-
/O.NEW.KMSO.WS.W.0016.090402T0600Z-090403T0600Z/
NORTHERN CLEARWATER MOUNTAINS-
858 PM PDT WED APR 1 2009

...WINTER STORM WARNING IN EFFECT UNTIL 11 PM PDT THURSDAY...

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A WINTER
STORM WARNING FOR SNOW AND BLOWING SNOW...WHICH IS IN EFFECT
UNTIL 11 PM PDT THURSDAY. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES...LOCALLY UP TO 10 INCHES
ARE EXPECTED BY THURSDAY EVENING. INCREASED AFTERNOON WINDS WILL
PRODUCE REDUCED VISIBILITIES FROM BLOWING AND DRIFTING SNOW. GREER
GRADE AND STATE HIGHWAY 11 FROM PIERCE TO HEADQUARTERS WILL BE
IMPACTED BY THIS STORM..

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS SIGNIFICANT AMOUNTS OF SNOW...
BLOWING SNOW...OR FREEZING RAIN ARE EXPECTED OR OCCURRING. STRONG
WINDS AND DANGEROUS WIND CHILLS ARE ALSO POSSIBLE.  THIS WILL
MAKE TRAVEL VERY HAZARDOUS OR IMPOSSIBLE.

&&

$$

IDZ006-007-021200-
/O.NEW.KMSO.WW.Y.0050.090402T0600Z-090402T2100Z/
SOUTHERN CLEARWATER MOUNTAINS-OROFINO/GRANGEVILLE REGION-
858 PM PDT WED APR 1 2009

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 2 PM PDT THURSDAY
ABOVE 2500 FEET...

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW AND BLOWING SNOW ABOVE 2500 FEET...
WHICH IS IN EFFECT UNTIL 2 PM PDT THURSDAY. 

TOTAL SNOW ACCUMULATIONS OF 3 TO 6 INCHES CAN BE EXPECTED WITH
LOCALLY HIGHER AMOUNTS UP TO 8 INCHES ABOVE 2500 FEET. LITTLE TO
NO ACCUMULATION EXPECTED BELOW. INCREASE AFTERNOON WINDS WILL
RESULT IN AREAS OF BLOWING AND DRIFTING SNOW AND REDUCED
VISIBILITIES. WHITEBIRD AND GREER GRADES AND COTTONWOOD WILL BE
IMPACTED BY THIS STORM WITH LOCAL BLIZZARD CONDITIONS POSSIBLE
OVER THE GRADES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...BLOWING
SNOW...OR FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE
PREPARED FOR SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE
CAUTION WHILE DRIVING.

&&

$$

MTZ006-021200-
/O.NEW.KMSO.WW.Y.0050.090402T0600Z-090403T0600Z/
BITTERROOT/SAPPHIRE MOUNTAINS-
958 PM MDT WED APR 1 2009

...WINTER WEATHER ADVISORY IN EFFECT UNTIL MIDNIGHT MDT THURSDAY
NIGHT ABOVE 4500 FEET FOR LOLO PASS...

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW ABOVE 4500 FEET FOR LOLO PASS...
WHICH IS IN EFFECT UNTIL MIDNIGHT MDT THURSDAY NIGHT. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 6 INCHES CAN BE EXPECTED ABOVE
4500 FEET WITH LOCALLY HIGHER AMOUNTS UP TO 8 INCHES OVER LOLO PASS.
THE MAIN AREA OF IMPACT WILL BE ALONG HIGHWAY 12 OVER LOLO PASS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...BLOWING
SNOW...OR FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE
PREPARED FOR SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE
CAUTION WHILE DRIVING.

&&

$$
6 follow-up statements
000 
WWUS45 KMSO 020934
WSWMSO

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MISSOULA MT
334 AM MDT THU APR 2 2009

.A PACIFIC STORM SYSTEM WILL MOVE THROUGH THE REGION TODAY
BRINGING ACCUMULATING SNOWFALL TO THE MOUNTAINS OF WESTERN MONTANA
AND CENTRAL IDAHO. THE NORTHERN AND CENTRAL CLEARWATER MOUNTAINS
AS WELL AS THE BITTERROOT RANGE ARE EXPECTED TO RECEIVE THE
HEAVIEST SNOWFALL TOTALS. THIS INCLUDES LOLO PASS AND THE HIGHER
TERRAIN OF THE CAMAS PRAIRIE INCLUDING WHITEBIRD AND GREER GRADES.
ALTHOUGH SNOW IS EXPECTED TO FALL THROUGH THE DAY REGION WIDE...SNOW
LEVELS ARE EXPECTED TO RISE DURING THE AFTERNOON LIMITING MOST
ACCUMULATIONS TO THE HIGHER TERRAIN. THIS WILL ESPECIALLY BE TRUE
ACROSS THE CAMAS PRAIRIE REGION OF EAST CENTRAL IDAHO. A ROBUST
COLD FRONT WILL PASS ACROSS THE AREA DURING THE AFTERNOON HOURS. INCREASED
WINDS ALONG THE FRONT MAY COMBINE WITH BURSTS OF HEAVY SNOWFALL
INITIATED BY THE FRONTAL PASSAGE TO PRODUCE AREAS OF BLOWING SNOW
AND REDUCED VISIBILITIES. LOCAL BLIZZARD OR WHITEOUT CONDITIONS
ARE POSSIBLE OVER WHITEBIRD AND GREER GRADES IN THE AFTERNOON.

IDZ005-021745-
/O.CON.KMSO.WS.W.0016.000000T0000Z-090403T0600Z/
NORTHERN CLEARWATER MOUNTAINS-
234 AM PDT THU APR 2 2009

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES...LOCALLY UP TO
10 INCHES ARE EXPECTED BY THIS EVENING. INCREASED AFTERNOON WINDS
WILL PRODUCE REDUCED VISIBILITIES FROM BLOWING SNOW. GREER GRADE
AND STATE HIGHWAY 11 FROM PIERCE TO HEADQUARTERS WILL BE IMPACTED
BY THIS STORM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS SIGNIFICANT AMOUNTS OF SNOW...
BLOWING SNOW...OR FREEZING RAIN ARE EXPECTED OR OCCURRING. STRONG
WINDS AND DANGEROUS WIND CHILLS ARE ALSO POSSIBLE.  THIS WILL
MAKE TRAVEL VERY HAZARDOUS OR IMPOSSIBLE.

&&

$$

IDZ006-007-021745-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090402T2100Z/
SOUTHERN CLEARWATER MOUNTAINS-OROFINO/GRANGEVILLE REGION-
234 AM PDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 2 PM PDT THIS
AFTERNOON ABOVE 2500 FEET...

A WINTER WEATHER ADVISORY ABOVE 2500 FEET REMAINS IN EFFECT UNTIL
2 PM PDT THIS AFTERNOON. 

TOTAL SNOW ACCUMULATIONS OF 3 TO 6 INCHES CAN BE EXPECTED WITH
LOCALLY HIGHER AMOUNTS ABOVE 2500 FEET. LITTLE TO NO ACCUMULATION
IS EXPECTED BELOW THIS ELEVATION. INCREASE AFTERNOON WINDS WILL
RESULT IN AREAS OF BLOWING SNOW AND REDUCED VISIBILITIES.
WHITEBIRD GRADE...GREER GRADE...AND COTTONWOOD WILL BE IMPACTED BY
THIS STORM WITH LOCAL BLIZZARD OR WHITEOUT CONDITIONS POSSIBLE
OVER THE GRADES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...BLOWING
SNOW...OR FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE
PREPARED FOR SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE
CAUTION WHILE DRIVING.

&&

$$

MTZ006-021745-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
BITTERROOT/SAPPHIRE MOUNTAINS-
334 AM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT ABOVE 4500 FEET...

A WINTER WEATHER ADVISORY ABOVE 4500 FEET REMAINS IN EFFECT UNTIL
MIDNIGHT MDT TONIGHT. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 6 INCHES CAN BE EXPECTED ABOVE
4500 FEET WITH LOCALLY HIGHER AMOUNTS OVER LOLO PASS AND IN THE
HIGHER TERRAIN. THE MAIN AREA OF IMPACT WILL BE ALONG HIGHWAY 12
OVER LOLO PASS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...BLOWING
SNOW...OR FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE
PREPARED FOR SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE
CAUTION WHILE DRIVING.

&&

$$
000 
WWUS45 KMSO 021339
WSWMSO

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MISSOULA MT
739 AM MDT THU APR 2 2009

.A PACIFIC STORM SYSTEM WILL MOVE THROUGH THE REGION TODAY
BRINGING ACCUMULATING SNOWFALL TO THE MOUNTAINS OF WESTERN
MONTANA AND CENTRAL IDAHO. THE NORTHERN AND CENTRAL CLEARWATER
MOUNTAINS AS WELL AS THE BITTERROOT RANGE ARE EXPECTED TO RECEIVE
THE HEAVIEST SNOWFALL TOTALS. THIS INCLUDES LOLO PASS AND THE
HIGHER TERRAIN OF THE CAMAS PRAIRIE INCLUDING WHITE BIRD AND GREER
GRADES. A ROBUST COLD FRONT WILL PASS ACROSS THE AREA DURING THE
AFTERNOON HOURS. INCREASED WINDS ALONG THE FRONT MAY COMBINE WITH
BURSTS OF HEAVY SNOWFALL INITIATED BY THE FRONTAL PASSAGE TO
PRODUCE AREAS OF BLOWING SNOW AND REDUCED VISIBILITIES. LOCAL
BLIZZARD OR WHITEOUT CONDITIONS ARE POSSIBLE OVER WHITE BIRD AND
GREER GRADES IN THE AFTERNOON.

IDZ005-022130-
/O.CON.KMSO.WS.W.0016.000000T0000Z-090403T0600Z/
NORTHERN CLEARWATER MOUNTAINS-
639 AM PDT THU APR 2 2009

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING. 

TOTAL SNOW ACCUMULATIONS OF 5 TO 10 INCHES ARE EXPECTED BY THIS
EVENING. INCREASED AFTERNOON WINDS WILL PRODUCE REDUCED
VISIBILITIES FROM BLOWING SNOW. GREER GRADE AND STATE HIGHWAY 11
FROM PIERCE TO HEADQUARTERS WILL BE IMPACTED BY THIS STORM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS SIGNIFICANT AMOUNTS OF SNOW...
BLOWING SNOW...OR FREEZING RAIN ARE EXPECTED OR OCCURRING. STRONG
WINDS AND DANGEROUS WIND CHILLS ARE ALSO POSSIBLE.  THIS WILL
MAKE TRAVEL VERY HAZARDOUS OR IMPOSSIBLE.

&&

$$

MTZ004-022130-
/O.EXA.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
LOWER CLARK FORK REGION-
739 AM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY IN EFFECT UNTIL MIDNIGHT MDT TONIGHT...

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW...WHICH IS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT.

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ALONG
THE INTERSTATE 90 CORRIDOR...PARTICULARLY FROM ST. REGIS TO LOOKOUT
PASS. ELSEWHERE...VALLEYS WILL GENERALLY SEE 2 TO 4 INCHES OF NEW
SNOW.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

IDZ006-007-022130-
/O.EXT.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
SOUTHERN CLEARWATER MOUNTAINS-OROFINO/GRANGEVILLE REGION-
639 AM PDT THU APR 2 2009

...WINTER WEATHER ADVISORY NOW IN EFFECT UNTIL 11 PM PDT THIS
EVENING ABOVE 2500 FEET...

THE WINTER WEATHER ADVISORY ABOVE 2500 FEET IS NOW IN EFFECT
UNTIL 11 PM PDT THIS EVENING. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ABOVE
2500 FEET. LITTLE TO NO ACCUMULATION IS EXPECTED BELOW THIS
ELEVATION. INCREASE AFTERNOON WINDS WILL RESULT IN AREAS OF
BLOWING SNOW AND REDUCED VISIBILITIES. WHITE BIRD GRADE...GREER
GRADE...AND COTTONWOOD WILL BE IMPACTED BY THIS STORM WITH LOCAL
BLIZZARD OR WHITEOUT CONDITIONS POSSIBLE OVER THE GRADES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...BLOWING
SNOW...OR FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE
PREPARED FOR SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE
CAUTION WHILE DRIVING.

&&

$$

MTZ006-022130-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
BITTERROOT/SAPPHIRE MOUNTAINS-
739 AM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT ABOVE 4500 FEET...

A WINTER WEATHER ADVISORY ABOVE 4500 FEET REMAINS IN EFFECT UNTIL
MIDNIGHT MDT TONIGHT. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ABOVE
4500 FEET WITH LOCALLY HIGHER AMOUNTS OVER LOLO PASS AND IN THE
HIGHER TERRAIN. THE MAIN AREA OF IMPACT WILL BE ALONG HIGHWAY
12 OVER LOLO PASS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...BLOWING
SNOW...OR FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE
PREPARED FOR SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE
CAUTION WHILE DRIVING.

&&

$$
000 
WWUS45 KMSO 021645
WSWMSO

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MISSOULA MT
1045 AM MDT THU APR 2 2009

IDZ005-030045-
/O.CON.KMSO.WS.W.0016.000000T0000Z-090403T0600Z/
NORTHERN CLEARWATER MOUNTAINS-
945 AM PDT THU APR 2 2009

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING. 

TOTAL SNOW ACCUMULATIONS OF 5 TO 10 INCHES ARE EXPECTED BY THIS
EVENING. INCREASED AFTERNOON WINDS WILL PRODUCE REDUCED
VISIBILITIES FROM BLOWING SNOW. STATE HIGHWAY 11 FROM PIERCE TO
HEADQUARTERS WILL BE IMPACTED BY THIS STORM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS SIGNIFICANT AMOUNTS OF SNOW AND BLOWING
SNOW ARE EXPECTED OR OCCURRING. THIS WILL MAKE TRAVEL VERY
HAZARDOUS OR IMPOSSIBLE.

&&

$$

MTZ004-030045-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
LOWER CLARK FORK REGION-
1045 AM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ALONG
THE INTERSTATE 90 CORRIDOR...PARTICULARLY FROM ST. REGIS TO
LOOKOUT PASS. ELSEWHERE...VALLEYS WILL GENERALLY SEE 2 TO
4 INCHES OF NEW SNOW.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

IDZ006-007-030045-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
SOUTHERN CLEARWATER MOUNTAINS-OROFINO/GRANGEVILLE REGION-
945 AM PDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING ABOVE 2500 FEET...

A WINTER WEATHER ADVISORY ABOVE 2500 FEET REMAINS IN EFFECT UNTIL
11 PM PDT THIS EVENING. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ABOVE
2500 FEET. LITTLE TO NO ACCUMULATION IS EXPECTED BELOW THIS
ELEVATION. INCREASE AFTERNOON WINDS WILL RESULT IN AREAS OF
BLOWING SNOW AND REDUCED VISIBILITIES. WHITE BIRD GRADE...GREER
GRADE...AND COTTONWOOD WILL BE IMPACTED BY THIS STORM WITH LOCAL
BLIZZARD OR WHITEOUT CONDITIONS POSSIBLE OVER THE GRADES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

MTZ006-030045-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
BITTERROOT/SAPPHIRE MOUNTAINS-
1045 AM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT ABOVE 4500 FEET...

A WINTER WEATHER ADVISORY ABOVE 4500 FEET REMAINS IN EFFECT UNTIL
MIDNIGHT MDT TONIGHT. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ABOVE
4500 FEET WITH LOCALLY HIGHER AMOUNTS OVER LOLO AND LOST TRAIL
PASSES. INCREASING WINDS THIS AFTERNOON COULD CAUSE BLOWING SNOW
AND REDUCED VISIBILITIES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$
000 
WWUS45 KMSO 021725
WSWMSO

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MISSOULA MT
1125 AM MDT THU APR 2 2009

IDZ005-030130-
/O.CON.KMSO.WS.W.0016.000000T0000Z-090403T0600Z/
NORTHERN CLEARWATER MOUNTAINS-
1025 AM PDT THU APR 2 2009

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING. 

TOTAL SNOW ACCUMULATIONS OF 5 TO 10 INCHES ARE EXPECTED BY THIS
EVENING. INCREASED AFTERNOON WINDS WILL PRODUCE REDUCED
VISIBILITIES FROM BLOWING SNOW. STATE HIGHWAY 11 FROM PIERCE TO
HEADQUARTERS WILL BE IMPACTED BY THIS STORM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS SIGNIFICANT AMOUNTS OF SNOW AND
BLOWING SNOW ARE EXPECTED OR OCCURRING. THIS WILL MAKE TRAVEL
VERY HAZARDOUS OR IMPOSSIBLE.

&&

$$

MTZ043-030130-
/O.EXA.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
POTOMAC/SEELEY LAKE REGION-
1125 AM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY IN EFFECT UNTIL MIDNIGHT MDT TONIGHT...

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW...WHICH IS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT.

ADDITIONAL SNOW ACCUMULATIONS OF 2 TO 4 INCHES CAN BE EXPECTED
IN THE SEELEY LAKE REGION THROUGH THURSDAY EVENING. ACCUMULATING
SNOW MAY CREATE HAZARDOUS DRIVING CONDITIONS ALONG HIGHWAY 83 AND
LOCAL AREA ROADS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

MTZ004-030130-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
LOWER CLARK FORK REGION-
1125 AM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ALONG
THE INTERSTATE 90 CORRIDOR...PARTICULARLY FROM ST. REGIS TO
LOOKOUT PASS. ELSEWHERE...VALLEYS WILL GENERALLY SEE 2 TO
4 INCHES OF NEW SNOW.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

IDZ006-007-030130-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
SOUTHERN CLEARWATER MOUNTAINS-OROFINO/GRANGEVILLE REGION-
1025 AM PDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING ABOVE 2500 FEET...

A WINTER WEATHER ADVISORY ABOVE 2500 FEET REMAINS IN EFFECT UNTIL
11 PM PDT THIS EVENING. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ABOVE
2500 FEET. LITTLE TO NO ACCUMULATION IS EXPECTED BELOW THIS
ELEVATION. INCREASE AFTERNOON WINDS WILL RESULT IN AREAS OF
BLOWING SNOW AND REDUCED VISIBILITIES. WHITE BIRD GRADE...GREER
GRADE...AND COTTONWOOD WILL BE IMPACTED BY THIS STORM WITH LOCAL
BLIZZARD OR WHITEOUT CONDITIONS POSSIBLE OVER THE GRADES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

MTZ006-030130-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
BITTERROOT/SAPPHIRE MOUNTAINS-
1125 AM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT ABOVE 4500 FEET...

A WINTER WEATHER ADVISORY ABOVE 4500 FEET REMAINS IN EFFECT UNTIL
MIDNIGHT MDT TONIGHT. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ABOVE
4500 FEET WITH LOCALLY HIGHER AMOUNTS OVER LOLO AND LOST TRAIL
PASSES. INCREASING WINDS THIS AFTERNOON COULD CAUSE BLOWING SNOW
AND REDUCED VISIBILITIES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$
000 
WWUS45 KMSO 022048
WSWMSO

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MISSOULA MT
248 PM MDT THU APR 2 2009

MTZ043-022200-
/O.CAN.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
POTOMAC/SEELEY LAKE REGION-
248 PM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS CANCELLED THE WINTER
WEATHER ADVISORY. 

SNOW SHOWERS CAN BE EXPECTED TO CONTINUE ACROSS THE SEELEY SWAN
VALLEY WITH LIGHT ACCUMULATIONS OF UP TO TWO INCHES THROUGH THE
EVENING HOURS. WHILE SNOW SHOWERS WILL REMAIN OVER THE VALLEY
AREA...HEAVY ACCUMULATIONS ARE NOT EXPECTED. THEREFORE THE WINTER
WEATHER ADVISORY HAS BEEN CANCELLED.

$$

IDZ005-030600-
/O.CON.KMSO.WS.W.0016.000000T0000Z-090403T0600Z/
NORTHERN CLEARWATER MOUNTAINS-
148 PM PDT THU APR 2 2009

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING. 

ADDITIONAL SNOW ACCUMULATIONS OF 3 TO 6 INCHES ARE EXPECTED
THROUGH THIS EVENING. BREEZY WEST WINDS WILL PRODUCE BLOWING SNOW
AND REDUCED VISIBILITIES AT TIMES. STATE HIGHWAY 11 FROM PIERCE TO
HEADQUARTERS WILL BE IMPACTED BY THIS STORM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS SIGNIFICANT AMOUNTS OF SNOW AND
BLOWING SNOW ARE EXPECTED OR OCCURRING. THIS WILL MAKE TRAVEL
VERY HAZARDOUS OR IMPOSSIBLE.

&&

$$

IDZ006-030600-
/O.EXT.KMSO.WW.Y.0050.000000T0000Z-090403T1200Z/
SOUTHERN CLEARWATER MOUNTAINS-
148 PM PDT THU APR 2 2009

...WINTER WEATHER ADVISORY NOW IN EFFECT UNTIL 5 AM PDT FRIDAY
ABOVE 2500 FEET...

THE WINTER WEATHER ADVISORY ABOVE 2500 FEET IS NOW IN EFFECT
UNTIL 5 AM PDT FRIDAY. 

ADDITIONAL SNOW ACCUMULATIONS OF 2 TO 5 INCHES CAN BE EXPECTED
ABOVE 2500 FEET. LITTLE TO NO ACCUMULATION IS EXPECTED BELOW THIS
ELEVATION. INCREASED WINDS WILL RESULT IN AREAS OF BLOWING SNOW
AND REDUCED VISIBILITIES AT TIMES. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

MTZ006-030600-
/O.EXT.KMSO.WW.Y.0050.000000T0000Z-090403T1200Z/
BITTERROOT/SAPPHIRE MOUNTAINS-
248 PM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY NOW IN EFFECT UNTIL 6 AM MDT FRIDAY
ABOVE 4500 FEET...

THE WINTER WEATHER ADVISORY ABOVE 4500 FEET IS NOW IN EFFECT
UNTIL 6 AM MDT FRIDAY. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ABOVE
4500 FEET WITH LOCALLY HIGHER AMOUNTS OVER LOLO AND LOST TRAIL
PASSES. BREEZY WEST WINDS COULD CAUSE BLOWING SNOW AND REDUCED
VISIBILITIES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

MTZ004-030600-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
LOWER CLARK FORK REGION-
248 PM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ALONG
THE INTERSTATE 90 CORRIDOR...PARTICULARLY FROM ST. REGIS TO
LOOKOUT PASS. ELSEWHERE...VALLEYS WILL GENERALLY SEE 2 TO 4 INCHES
OF NEW SNOW.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

IDZ007-030600-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
OROFINO/GRANGEVILLE REGION-
148 PM PDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING ABOVE 2500 FEET...

A WINTER WEATHER ADVISORY ABOVE 2500 FEET REMAINS IN EFFECT UNTIL
11 PM PDT THIS EVENING. 

WIDESPREAD SNOW SHOWERS PERSIST THROUGH THE EVENING MAINLY IN THE
LOWER HILLS NORTH OF HIGHWAY 12 FROM KOOSKIA TO NEAR OROFINO. AN
ADDITIONAL 3 TO 6 INCHES OF SNOW ARE EXPECTED ABOVE 2500 FEET.
LITTLE TO NO ACCUMULATION IS EXPECTED BELOW THIS ELEVATION.
BREEZY WEST WINDS WILL RESULT IN AREAS OF BLOWING SNOW AND
REDUCED VISIBILITIES. THE MAIN IMPACT WILL BE ON THE GREER GRADE
TO WEIPPE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$
000 
WWUS45 KMSO 030347 AAA
WSWMSO

URGENT - WINTER WEATHER MESSAGE...UPDATED
NATIONAL WEATHER SERVICE MISSOULA MT
947 PM MDT THU APR 2 2009

IDZ005-030500-
/O.CAN.KMSO.WS.W.0016.000000T0000Z-090403T0600Z/
NORTHERN CLEARWATER MOUNTAINS-
847 PM PDT THU APR 2 2009

...WINTER STORM WARNING IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS CANCELLED THE WINTER
STORM WARNING. 

SNOW SHOWERS WILL CONTINUE OVERNIGHT...BUT WIDESPREAD
ACCUMULATIONS ARE NOT EXPECTED. THEREFORE THE WINTER STORM WARNING
HAS BEEN CANCELLED. LOCAL ACCUMULATIONS WILL GENERALLY REMAIN
BETWEEN 1 TO 3 INCHES POSSIBLE BY MORNING. ACCUMULATIONS WILL BE A
DIRECT RESULT OF HEAVIER ISOLATED BANDS.

$$

MTZ004-030500-
/O.CAN.KMSO.WW.Y.0050.000000T0000Z-090403T0600Z/
LOWER CLARK FORK REGION-
947 PM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS CANCELLED THE WINTER
WEATHER ADVISORY. 

SNOW SHOWERS WILL CONTINUE TO DECREASE THE REMAINDER OF THE EVENING
ENDING WIDESPREAD ACCUMULATING SNOW. THEREFORE THE SNOW ADVISORY
HAS BEEN CANCELLED. 

$$

IDZ007-031200-
/O.EXT.KMSO.WW.Y.0050.000000T0000Z-090403T1200Z/
OROFINO/GRANGEVILLE REGION-
847 PM PDT THU APR 2 2009

...WINTER WEATHER ADVISORY NOW IN EFFECT UNTIL 5 AM PDT FRIDAY
ABOVE 2500 FEET...

THE WINTER WEATHER ADVISORY ABOVE 2500 FEET IS NOW IN EFFECT
UNTIL 5 AM PDT FRIDAY. 

WIDESPREAD SNOW SHOWERS WILL PERSIST THROUGH THE OVERNIGHT HOURS.
AN ADDITIONAL 3 TO 6 INCHES OF SNOW ARE EXPECTED ABOVE 2500 FEET.
LITTLE TO NO ACCUMULATION IS EXPECTED BELOW THIS ELEVATION. BREEZY
WEST WINDS WILL RESULT IN AREAS OF BLOWING SNOW AND REDUCED
VISIBILITIES. THE MAIN IMPACT WILL BE ON THE GREER GRADE TO
WEIPPE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

IDZ006-031200-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T1200Z/
SOUTHERN CLEARWATER MOUNTAINS-
847 PM PDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 AM PDT
FRIDAY ABOVE 2500 FEET...

A WINTER WEATHER ADVISORY ABOVE 2500 FEET REMAINS IN EFFECT UNTIL
5 AM PDT FRIDAY. 

ADDITIONAL SNOW ACCUMULATIONS OF 2 TO 5 INCHES CAN BE EXPECTED
ABOVE 2500 FEET. LITTLE TO NO ACCUMULATION IS EXPECTED BELOW THIS
ELEVATION. INCREASED WINDS WILL RESULT IN AREAS OF BLOWING SNOW
AND REDUCED VISIBILITIES AT TIMES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

MTZ006-031200-
/O.CON.KMSO.WW.Y.0050.000000T0000Z-090403T1200Z/
BITTERROOT/SAPPHIRE MOUNTAINS-
947 PM MDT THU APR 2 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 AM MDT
FRIDAY ABOVE 4500 FEET...

A WINTER WEATHER ADVISORY ABOVE 4500 FEET REMAINS IN EFFECT UNTIL
6 AM MDT FRIDAY. 

TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED ABOVE
4500 FEET WITH LOCALLY HIGHER AMOUNTS OVER LOLO AND LOST TRAIL
PASSES. BREEZY WEST WINDS COULD CAUSE BLOWING SNOW AND REDUCED
VISIBILITIES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW AND BLOWING
SNOW WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

What forecasters said that day

The local office's own words before this winter storm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Missoula, MT wrote its last area forecast discussion before this winter storm warning went out at Apr 1, 1:55 PM PDT, 7 hours 3 minutes earlier.

Area forecast discussion, Apr 1, 1:55 PM PDT, 7 hours 3 minutes before
AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE MISSOULA MT
255 PM MDT WED APR 1 2009

WINTER WEATHER HIGHLIGHTS ARE IN EFFECT FOR THE NORTHWEST
MONTANA MOUNTAIN PASSES. SEE WWW.WEATHER.GOV/MISSOULA FOR DETAILS

.DISCUSSION...ANOTHER WINTER WEATHER DISTURBANCE WILL MOVE
THROUGH THE NORTHERN ROCKIES BEGINNING LATE THIS EVENING THROUGH
THURSDAY EVENING. PLENTY OF MOISTURE AND DYNAMICS IN THE FORM OF
OROGRAPHIC LIFT ARE AVAILABLE TO PRODUCE SIGNIFICANT
PRECIPITATION. SNOW LEVELS WILL START FAIRLY LOW BUT THEN QUICKLY
RISE THURSDAY MORNING THROUGH THE AFTERNOON HOURS TO AROUND 5000
FEET IN CENTRAL IDAHO AND WEST CENTRAL MONTANA AND AROUND 4000
FEET IN NORTHWEST MONTANA. BECAUSE OF THE HIGHER SNOW LEVELS THE
ONLY IMPACT FROM ACCUMULATING SNOW WILL BE OVER THE MOUNTAIN
PASSES. THERE IS UNCERTAINTY AS TO HOW MUCH SNOW OR RAIN/SNOW MIX
LOLO PASS WILL RECEIVE THUS THEY HAVE NOT BEEN INCLUDED IN ANY
WINTER WEATHER HIGHLIGHTS NOW BUT MAY BE NEEDED LATER.

THURSDAY NIGHT AND FRIDAY...THE COLD FRONT WILL PUSH THROUGH THE REGION
LATE THURSDAY AFTERNOON AND EVENING. COLDER AND MORE UNSTABLE AIR
BEHIND THE FRONT WILL BE CONDUCIVE FOR WIDESPREAD SNOW
SHOWERS THROUGH FRIDAY AFTERNOON. ALONG WITH THE COLD FRONT WILL
BE AN AMPLIFYING TROF OVER THE ENTIRE WEST WITH THE MAJORITY OF
ENERGY FORMING IN THE GREAT BASIN. MODELS ARE INDICATING A 700 MB
LOW DEVELOPING IN THE NORTHERN BRANCH OF THIS SPLIT FLOW IN SOUTH
CENTRAL IDAHO. THIS MID LEVEL FEATURE IN ADDITION TO WRAP AROUND
MOISTURE BEHIND THE EXITING SURFACE LOW AND DEFORMATION BOUNDARY
COULD BRING A POTENTIAL FOR A BAND OF SIGNIFICANT SNOWFALL. THE
UNCERTAINTY WITH THIS SOLUTION IS MODELS DO DIFFER WITH THE
POSITIONING OF THIS BOUNDARY ANYWHERE FROM SOUTH CENTRAL OR EAST
CENTRAL IDAHO TO SOUTHWEST MONTANA. A HAZARDOUS WEATHER OUTLOOK
WILL BE POSTED FOR THESE AREAS.

A SHORTWAVE RIDGE WILL MOVE INTO THE NORTHWEST UNITED STATES ON
SATURDAY AND INTO THE NORTHERN ROCKIES SUNDAY. THIS WILL DRY OUT
AND WARM UP THE REGION THROUGH MONDAY. UNCERTAINTY STILL EXIST
BEYOND MONDAY WITH THE GFS AND ITS ENSEMBLES BRINGING A LOW
PRESSURE SYSTEM THROUGH SOUTHERN IDAHO WHICH PRODUCES THE
POTENTIAL OF SOME RAIN AND SNOW. BOTH THE ECMWF AND CANADIAN
MODELS HOWEVER KEEP THIS SYSTEM SOUTH OF IDAHO AND TAKE IT INTO
THE GREAT PLAINS. WITH THE GFS BEING THE OUTLIER KEPT A SMALL
CHANCE OF PRECIPITATION ACROSS THE SOUTHERN PORTION OF THE REGION
AND WENT WITH THE WARMER TEMPERATURES THE OTHER TWO MODELS
SUGGESTED.

&&

.AVIATION...SHOWER ACTIVITY WILL GRADUALLY INCREASE THIS EVENING AND
OVER NIGHT AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. EXPECT TO
SEE A GRADUAL LOWERING OF CEILINGS THROUGH THE NIGHT AS A WARM
FRONT MOVES THROUGH THE REGION AND SPREADS PRECIPITATION FIRST
INTO NORTH CENTRAL IDAHO...AND THEN INTO WESTERN MONTANA BY EARLY
MORNING. AS CEILINGS LOWER...EXPECT MOUNTAINS AND PASSES TO BECOME
OBSCURED. THE SNOW LEVEL WILL GRADUALLY INCREASE TO BETWEEN 4000
AND 5000 FEET BY TOMORROW AFTERNOON...BRINGING RAIN OR A RAIN SNOW
MIX TO THE VALLEYS AND SNOW OVER THE HIGHER TERRAIN. VISIBILITY
WILL BECOME RESTRICTED LATE TONIGHT AND TOMORROW MORNING...ESPECIALLY
IN LOCATIONS RECEIVING SNOW. AIRFIELDS KMSO...KGPI AND KSMN CAN
ALL EXPECT DETERIORATING CONDITIONS AROUND 12Z THURSDAY WITH KBTM
DETERIORATING AROUND 17Z THURSDAY.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO MIDNIGHT
     MDT THURSDAY NIGHT FOR LOWER CLARK FORK REGION.

     WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO MIDNIGHT MDT
     THURSDAY NIGHT FOR WEST GLACIER REGION.

ID...NONE.
&&

SHORT TERM...RPN
LONG TERM....LOEFFELBEIN
AVIATION...VIA
Hazardous weather outlook, Apr 1, 1:54 PM PDT, 7 hours 4 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MISSOULA MT
254 PM MDT WED APR 1 2009

IDZ006-MTZ006-021100-
SOUTHERN CLEARWATER MOUNTAINS-BITTERROOT/SAPPHIRE MOUNTAINS-
254 PM MDT WED APR 1 2009 /154 PM PDT WED APR 1 2009/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
IDAHO AND WEST CENTRAL MONTANA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

SNOW SHOWERS WILL INCREASE OVER THE AREA TONIGHT AHEAD OF AN
APPROACHING WEATHER SYSTEM.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

ANOTHER SPRINGTIME SNOW STORM WILL MOVE THROUGH THE NORTHERN ROCKIES
THURSDAY AND THURSDAY NIGHT BRINGING SIGNIFICANT SNOWFALL
ACCUMULATIONS MAINLY TO THE BITTERROOT AND CLEARWATER MOUNTAIN
RANGES. THE MAIN IMPACT WILL BE TO PEOPLE TRAVELING OVER LOLO
PASS WHERE MODERATE SNOW ACCUMULATIONS ARE POSSIBLE BY FRIDAY
MORNING.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

IDZ010-021100-
EASTERN LEMHI COUNTY-
254 PM MDT WED APR 1 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
IDAHO.

.DAY ONE...THIS AFTERNOON AND TONIGHT

SNOW SHOWERS WILL INCREASE OVER THE AREA TONIGHT AHEAD OF AN
APPROACHING WEATHER SYSTEM.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

ANOTHER SPRINGTIME SNOW STORM WILL MOVE THROUGH SOUTHERN LEMHI
COUNTY DURING THE DAY FRIDAY. STRONG SURFACE WINDS COULD
POTENTIALLY COMBINE WITH MODERATE SNOWFALL TO PRODUCE DIFFICULT AND
DANGEROUS DRIVING CONDITIONS SOUTH OF SALMON ON HIGHWAY 28 AND US
HIGHWAY 93. STAY TUNED FOR UPDATES AND THE POSSIBLE ISSUANCE OF
WINTER WEATHER HIGHLIGHTS.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 1, 8:58 PM PDTWinter Weather AdvisoryMSOClearwater, Idaho32 hr

Nearby

Winter Storm Warnings in Idaho, 2009Every winter storm warning in 2009

Sources

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