Special Weather Statement, NWS Missoula, MT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
352 AM MDT MON JUL 25 2011

.DISCUSSION...A SPOKE OF ENERGY IN ADVANCE OF AN APPROACHING
WEATHER SYSTEM HAS ENHANCED MOIST UNSTABLE AIR AT THE MID-LEVELS
OF THE ATMOSPHERE ACROSS IDAHO AND INTO PORTIONS OF WESTERN
MONTANA THIS MORNING. RELATIVELY DRY AIR AT THE LOWER LEVELS OF
THE ATMOSPHERE WILL LIMIT THE AMOUNT OF RAIN REACHING THE SURFACE
THIS MORNING. AS THE AIR MASS BECOMES INCREASINGLY MORE MOIST AND
UNSTABLE THIS AFTERNOON...THE THUNDERSTORMS THREAT BECOMES MORE
PROMINENT ACROSS NORTHERN IDAHO AND WESTERN MONTANA. THE WEATHER
SYSTEM MOVING ACROSS THE PACIFIC NORTHWEST WILL LIKELY ADD EXTRA
ATMOSPHERIC LIFT MAKING IT A FAVORABLE ENVIRONMENT FOR A FEW
STRONG STORMS CAPABLE OF PRODUCING SMALL HAIL AND GUSTY WINDS.
SPEAKING OF WINDS...THE PATTERN IS SETTING UP FOR WINDY CONDITIONS
ACROSS LEMHI COUNTY THIS AFTERNOON AS WINDS ALOFT MIX TO THE
SURFACE. THE PRIMARY WEATHER SYSTEM WILL SWEEP ACROSS THE NORTHERN
ROCKIES REGION TONIGHT. WHILE THE THUNDERSTORM POTENTIAL WILL
CONTINUE TONIGHT...INDIVIDUAL STORMS SHOULD SEE A DECREASE IN
INTENSITY.

TUESDAY AND WEDNESDAY...SUBSEQUENT WAVES OF ENERGY RIPPLING
THROUGH SOUTHWEST CANADA WILL PROLONG THE EXISTENCE A LOW
AMPLITUDE TROUGH OF LOW PRESSURE OVER THE REGION. THIS PATTERN
WILL PROMOTE SLIGHTLY COOLER THAN NORMAL DAY-TIME TEMPERATURES
...BREEZY AFTERNOON WINDS AND A CHANCE OF PRECIPITATION NEAR THE
CANADIAN BORDER.

THURSDAY THROUGH SUNDAY...THE UPPER FLOW PATTERN WILL CONTINUE TO
BE WESTERLY...BUT THE ATMOSPHERE WILL GRADUALLY WARM WITH THE BULK
OF THE MOISTURE MOVING FARTHER NORTH INTO CANADA. BY SUNDAY...THE
UPPER FLOW BECOMES MORE SOUTHWESTERLY DRAWING EVEN WARMER AIR
NORTHWARD INTO THE REGION.

&&

.AVIATION...MOISTURE AND INSTABILITY WILL BE INCREASING OVER
NORTHERN IDAHO AND WESTERN MONTANA IN ADVANCE OF A WEATHER SYSTEM
MOVING ACROSS THE PACIFIC NORTHWEST TODAY. WHILE A FEW SHOWERS
HAVE ALREADY DEVELOPED AND WERE MOVING NORTHEAST ACROSS NORTHERN
IDAHO AND PORTIONS OF WESTERN MONTANA THIS MORNING...STORMS WILL
BE GROWING IN NUMBERS AND GAIN INTENSITY THIS AFTERNOON/EVENING.
CLOUDS WILL BE HIGH-BASED INITIALLY THIS MORNING. LOWER CEILINGS
AND PARTIAL MOUNTAIN OBSCUREMENT IS LIKELY IN ASSOCIATION WITH
SHOWERS AND THUNDERSTORMS. AFTERNOON STORMS WILL BE CAPABLE OF
PRODUCING SMALL HAIL AND GUSTY WINDS. ALL AIRFIELDS WILL BE
IMPACTED BY THUNDERSTORMS TODAY AND TONIGHT.

&&

NOTE: FLOOD WATCHES...WARNINGS AND ADVISORIES WILL NOT BE LISTED BELOW.

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
ID...NONE.
&&

MSJ

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MISSOULA MT
125 PM MDT MON JUL 25 2011

IDZ009-010-252000-
EASTERN LEMHI COUNTY-WESTERN LEMHI COUNTY-
125 PM MDT MON JUL 25 2011

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL LEMHI COUNTY UNTIL 200 PM
MDT...

AT 123 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR SALMON...MOVING NORTHEAST AT 40 MPH.

WIND GUSTS UP TO 30 MPH ARE EXPECTED WITH THIS STORM.

LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE...SALMON AND CARMEN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF THREATENING WEATHER APPROACHES YOUR AREA...GO INDOORS AND STAY
AWAY FROM WINDOWS. IF YOU ARE CAUGHT OUTSIDE...MOVE TO A WELL
PROTECTED AREA.

&&

LAT...LON 4512 11406 4547 11378 4542 11376 4539 11372
      4533 11372 4528 11368 4526 11368 4523 11364
      4503 11384
TIME...MOT...LOC 1925Z 213DEG 34KT 4515 11388