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000
FXUS66 KOTX 170042 CCA
AFDOTX

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SPOKANE WA
542 PM PDT SUN JUN 16 2013

.SYNOPSIS...
THE CHANCE FOR SHOWERS AND THUNDERSTORMS BEGINS TONIGHT OVER THE
CASCADES, AND GRADUALLY BROADENS ACROSS THE ENTIRE INLAND
NORTHWEST MONDAY THROUGH WEDNESDAY NIGHT. HIGH TEMPERATURES WILL PEAK
TODAY AND BEGIN A COOLING TREND ON MONDAY. DOWNRIGHT WET, COOL
CONDITIONS ARRIVE BY WEDNESDAY, WITH A DRYING AND WARMING TREND
LATE IN THE WEEK.

&&

DISCUSSION...

TONIGHT THROUGH MONDAY NIGHT: UPPER LEVEL RIDGE IS SLOWLY MOVING
EAST AS THE CLOSED LOW OFF THE PACIFIC NORTHWEST COAST CONTINUES
TO SIT AND SPIN. THERE IS A WAVE MOVING UP THE WA COAST THIS
AFTERNOON. IN RESPONSE TO THAT THERE IS A CHANCE OF SHOWERS AND
THUNDERSTORMS THROUGH THE AFTERNOON AND EVENING...MAINLY ACROSS
THE CASCADES, WATERVILLE PLATEAU, AND OKANOGAN VALLEY AND
HIGHLANDS. THERE IS A SLIGHT CHANCE OF SOME ELEVATED CONVECTION
OVERNIGHT AND INTO EARLY MONDAY MORNING...MAINLY ACROSS NORTHERN WA
AND ID. THE CLOSED LOW WILL CONTINUE TO BRING WAVES OF ENERGY
INTO THE REGION FOR PERIODS OF SHOWERS AND THUNDERSTORMS MONDAY
AND MONDAY NIGHT AS WELL. TEMPERATURES WILL BE ABOVE AVERAGE FOR THIS
TIME OF THE YEAR. /NISBET

TUES THROUGH WED NT: WE FOCUSED ON THE THUNDER AND PCPN AMNT
THREATS, NOT ONLY WITH DAYTIME HEATING EACH DAY, BUT ALSO THE MORE
CHALLENGING FCST OF NOCTURNAL/OVERNIGHT THUNDER. AND DUE TO THE
SLOW PROGRESSION OF THE OFFSHORE UPPER LOW, WE`LL KEEP A SUSTAINED
SOUTHERLY MOISTURE FETCH OVER THE REGION IN PLACE EACH DAY. THE
NOCTURNAL THREAT WILL BE BOTH LATE MON NT INTO TUES MORNING,
FOLLOWED BY YET ANOTHER LATE TUES NT. THIS TUES NT FEATURE WILL BE
FOLLOWED BY THE EJECTION EAST OF THE ALMOST STATIONARY UPPER LOW
CURRENTLY JUST OFF THE PAC NW COAST. IT IS THIS EJECTION THAT WILL
PRODUCE A RAPID CHANGE IN WEATHER... FROM THE CURRENTLY WARM/DRY
CONDITIONS TO A MUCH COOLER AND VERY SHOWERY (THUNDER) REGIME WED.
THE NIGHTTIME SHOWER/THUNDER THREAT DOESN`T ACCOMPANY A WELL-
DEFINED VORT MAX MON NT/TUES MORNING, UNLIKE THE STRONG WAVE
EJECTING EAST LATE TUES NT. THESE QUICK-HITTING SERIES OF WAVES
AHEAD OF THE UPPER TROUGH SHOWS A STRONG SIGNAL OF MOIST
CONVECTIVE INSTABILITY ABOVE 700MB. FOR THE AFTERNOON THUNDER
THREATS...TUES AND WED WILL BE OUR BEST CHANCES OF THUNDER AS THE
UPPER LOW BEGINS TO EJECT INLAND. MODEL GUIDANCE IS CRANKING OUT
UNCAPPED ML CAPES OF 400 TO 800 J/KG BY LATE AFTERNOON
TUES...LIKELY HELPED FROM AFTERNOON INSOLATION. WED WILL BE COOLER
WITH A MUCH HIGHER COVERAGE OF SHOWERS. EMBEDDED STRONG
THUNDERSTORMS MAY BE POSSIBLE WITH DEEP LAYER SHEAR OF 40 TO 45
KTS. WITH A STEERING FLOW OF CLOSE TO 35 KTS FROM THE SOUTH, THESE
THUNDERSTORMS TUES WILL BE QUICK MOVERS. OBVIOUSLY, WIND AND HAIL
WILL BE THE MAIN THREATS. MORE RAIN SHOULD FALL ALONG THE CASCADES
WITH TRAINING STORMS. BZ

THURSDAY THROUGH THE WEEKEND...THIS PERIOD OF THE EXTENDED
FORECAST SHOULD REFLECT THE UPPER LOW PRESSURE MOVING SLOWLY EAST,
AND THEN EXITING THE INLAND NORTHWEST. BUT IT IS NOT IN A HURRY
TO DO SO. IN FACT, IF SOME OF THE EXTENDED MODELS ARE CORRECT,
PARTS OF THE REGION COULD BE DEALING WITH THIS SYSTEM THROUGH THE
WEEKEND. PRECIPITATION CHANCES WEREN`T CHANGED DRAMATICALLY, AND
SHOW A DECREASING TREND FROM FRIDAY ONWARD. HOWEVER, FUTURE
FORECASTS PRECIPITATION CHANCES MAY NEED TO BE INCREASED, AT
LEAST OVER THE NORTH AND EASTERN PORTIONS OF OUR FORECAST AREA. AS
FAR AS TEMPERATURES GO, THURSDAY LOOKS TO BE THE COLDEST DAY, WITH
A MODERATING TREND TOWARD NORMAL INTO THE WEEKEND. TY

AVIATION...
0Z TAFS: NO SIGNIFICANT CHANGES TO THE 0Z TAF PACKAGE. SHOWER
COVERAGE OVER THE CASCADES HAS BEEN LESS THAN IMPRESSIVE SO FAR
BUT STILL EXPECTING THE POSSIBILITY OF ISOLATED ELEVATED
CONVECTION OVERNIGHT. KEPT THE MENTION OF CBS AT ALL SITES AND
ADDED WIND SHIFTING AROUND TO THE SOUTHWEST AND INCREASING LATE
TONIGHT AND BECOMING GUSTY LATE MORNING AND EARLY AFTERNOON.

&&

.PRELIMINARY POINT TEMPS/POPS...
SPOKANE        57  81  55  75  50  63 /  20  20  40  60  80  80
COEUR D`ALENE  55  80  55  75  50  62 /  10  20  30  60  80  90
PULLMAN        50  79  50  72  46  60 /  10  10  30  60  70  70
LEWISTON       58  88  57  82  54  66 /  10  10  20  50  70  70
COLVILLE       54  81  53  79  50  64 /  20  40  40  80  80  90
SANDPOINT      49  80  52  81  48  60 /  10  30  40  60  90  90
KELLOGG        54  79  54  80  50  58 /  10  20  30  40  90  90
MOSES LAKE     59  86  57  75  53  71 /  20  20  40  60  50  40
WENATCHEE      62  82  59  74  55  69 /  20  10  30  50  50  40
OMAK           55  82  54  77  52  67 /  30  20  40  70  60  70

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
WA...NONE.
&&

$$