Special Weather Statement, NWS Spokane, WA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
1057 PM PDT Thu Jul 19 2012

.SYNOPSIS...
Thunderstorm chances will increase from south to north beginning
late this afternoon through the overnight hours. Then on Friday the
stage is being set for a significant bout of thunderstorms. Some
of the storms could be severe and produce very heavy rains. By
the weekend the weather will dry out for most locations. Another
upper level low will cross the region Sunday night and Monday
resulting in a chance of showers for locations north of highway 2.
The low will exit by Tuesday afternoon with dry and seasonably
warm weather to follow.

&&

.DISCUSSION...
Updated the forecast mainly to change the wording from chances to
scattered showers and thunderstorms over much of the region tonight.
The best Theta E air at low to mid levels remains southeast of a
line from Moses Lake to Sandpoint. This is where I expect most of
the thunderstorm activity to remain through midnight. This juicier
air will expand to the northwest through the overnight hours.
However, I expect showers and thunderstorms to be fairly sporadic
until we get some better forcing with a shortwave disturbance
rotating around the upper level low that is spinning over coastal
OR.  This wave is moving through central OR late this evening and
should spark off another round of thunderstorms from south to north
through the overnight hours. I don't think we will see much in the
way of severe thunderstorms until the main low gets ejected across
the region late tomorrow morning through tomorrow afternoon. /SVH

&&

.AVIATION...
06Z TAFs: A moist and unstable air mass will keep the possibility of
showers and thunderstorms through the late evening hours. However,
these showers and thunderstorms should be fairly sporadic until we
get some better forcing late tonight with a weak wave rotating
around the parent low off coastal Oregon. This disturbance will be
moving into southern WA after midnight with more widespread
thunderstorm activity expected. These storms will feature the
possibility for some heavy rain...small hail...and gusty outflow
winds. The upper level low over coastal Oregon will eject
northeastward into the region late tomorrow morning through late
tomorrow afternoon. This will give us our best chance for strong to
severe thunderstorms with very heavy rain...large hail...and strong
gusty winds possible with some of the stronger cells. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        68  81  59  80  59  83 /  40  70  50   0  10  10
Coeur d'Alene  63  82  57  80  55  83 /  40  80  60   0  10  10
Pullman        63  80  54  81  52  80 /  40  60  20  10  10  10
Lewiston       73  91  63  90  62  90 /  40  50  10  10  10  10
Colville       62  87  57  82  55  84 /  20  80  60  10  10  10
Sandpoint      59  82  56  79  51  82 /  30  80  60  20  10  10
Kellogg        62  83  57  79  55  84 /  50  70  60  10  10  10
Moses Lake     68  84  59  84  58  86 /  40  60  10   0  10  10
Wenatchee      69  84  62  85  61  83 /  50  60  10   0  10  10
Omak           64  84  59  85  57  84 /  30  80  40   0  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Flash Flood Watch from 5 AM PDT Friday through Friday evening
     for Central Panhandle Mountains-Coeur d'Alene Area-Idaho
     Palouse-Northern Panhandle.

WA...Flash Flood Watch from 5 AM PDT Friday through Friday evening
     for Northeast Mountains-Okanogan Highlands-Okanogan Valley-
     Spokane Area-Upper Columbia Basin-Waterville Plateau.

     Flash Flood Watch through Friday afternoon for East Slopes
     Northern Cascades-Wenatchee Area.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SPOKANE WA
546 AM PDT THU JUL 19 2012

IDZ001>004-026-027-WAZ031>038-041>044-201300-
NORTHERN PANHANDLE-COEUR D'ALENE AREA-IDAHO PALOUSE-
CENTRAL PANHANDLE MOUNTAINS-LEWISTON AREA-
LEWIS AND SOUTHERN NEZ PERCE COUNTIES-NORTHEAST BLUE MOUNTAINS-
LOWER GARFIELD AND ASOTIN COUNTIES-WASHINGTON PALOUSE-
MOSES LAKE AREA-UPPER COLUMBIA BASIN-SPOKANE AREA-
NORTHEAST MOUNTAINS-OKANOGAN HIGHLANDS-WENATCHEE AREA-
EAST SLOPES NORTHERN CASCADES-OKANOGAN VALLEY-WATERVILLE PLATEAU-
546 AM PDT THU JUL 19 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH IDAHO...
NORTH CENTRAL IDAHO...CENTRAL WASHINGTON...EAST CENTRAL
WASHINGTON...NORTH CENTRAL WASHINGTON...NORTHEAST WASHINGTON AND
SOUTHEAST WASHINGTON.

.DAY ONE...TODAY AND TONIGHT

THERE IS AN INCREASING RISK FOR THUNDERSTORMS THIS EVENING INTO
THE OVERNIGHT HOURS. STORMS WILL DEVELOP ACROSS NORTHERN OREGON
THIS AFTERNOON AND SPREAD NORTHWARD THIS EVENING. ISOLATED STORMS
NEAR THE WASHINGTON...OREGON BORDER MAY BECOME STRONG TO LOCALLY
SEVERE LATE THIS AFTERNOON INTO THE EVENING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

A STRONG STORM SYSTEM WILL LIFT THROUGH THE REGION ON FRIDAY LEADING
TO A GOOD CHANCE FOR THUNDERSTORMS REGION-WIDE. THERE IS AN
INCREASING LIKELIHOOD THAT SOME STORMS MAY BE STRONG TO SEVERE
CAPABLE OF DAMAGING WIND GUSTS...LARGE HAIL...AND VERY HEAVY
RAINFALL.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SPOKANE WA
709 PM PDT THU JUL 19 2012

IDZ003-004-026-200300-
NEZ PERCE ID-LATAH ID-
709 PM PDT THU JUL 19 2012

THE NATIONAL WEATHER SERVICE IN SPOKANE HAS ISSUED A

SIGNIFICANT WEATHER ADVISORY FOR...
  NORTHEASTERN NEZ PERCE COUNTY IN NORTH CENTRAL IDAHO
  SOUTHEASTERN LATAH COUNTY IN THE PANHANDLE OF IDAHO

UNTIL 800 PM PDT

AT 706 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR CULDESAC..MOVING NORTH AT 25 MPH.

HAIL UP TO THE SIZE OF PENNIES AND WIND GUSTS UP TO 40 MPH ARE
EXPECTED WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
   JULIAETTA...
   KENDRICK...
   TROY...

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

LAT...LON 4635 11679 4676 11686 4674 11632 4663 11632
      4662 11633 4662 11644 4651 11644 4650 11638
      4633 11653
TIME...MOT...LOC 0209Z 187DEG 23KT 4642 11663

VAN HORN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SPOKANE WA
1226 AM PDT FRI JUL 20 2012

WAZ042-043-200815-
OKANOGAN WA-
1226 AM PDT FRI JUL 20 2012

THE NATIONAL WEATHER SERVICE IN SPOKANE HAS ISSUED A

SIGNIFICANT WEATHER ADVISORY FOR...
  WESTERN OKANOGAN COUNTY IN NORTH CENTRAL WASHINGTON

UNTIL 115 AM PDT

AT 1223 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR METHOW..MOVING NORTHWEST AT 35 MPH.

HAIL UP TO THE SIZE OF PENNIES AND WIND GUSTS UP TO 40 MPH ARE
POSSIBLE WITH THIS STORM. HEAVY RAIN WILL ALSO OCCUR UNDER THIS
STORM.

LOCATIONS IMPACTED INCLUDE...
   CARLTON...
   TWISP...
   WINTHROP...

IF THREATENING WEATHER APPROACHES YOUR AREA...TAKE SHELTER IN A
STURDY BUILDING.

LAT...LON 4850 12061 4870 11999 4813 11974 4803 12008
TIME...MOT...LOC 0726Z 157DEG 31KT 4817 11997

FX