[ W WA | SW WA and W OR | SE WA and NE OR | NE WA and N ID ]

Western Washington


930 
FXUS66 KSEW 041601
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
900 AM PDT SAT JUL 4 2015

.SYNOPSIS...THE WARM SPELL WILL CONTINUE THROUGH THE MIDDLE OF NEXT 
WEEK. COOLER WEATHER WILL ARRIVE LATE NEXT WEEK AS AN UPPER TROUGH 
NEARS THE AREA AND ONSHORE FLOW INCREASES.

&&

.SHORT TERM...WELL ABOVE AVERAGE TEMPS WILL CONTINUE INTO THE FIRST 
HALF OF NEXT WEEK. EVEN THE COAST WILL WARM UP ON SUNDAY AS THE 
SURFACE THERMAL TROUGH EXPANDS WWD OVER THE COASTAL WATERS. A HEAT 
ADVISORY IS IN EFFECT THROUGH SUNDAY EVENING FOR INLAND AREAS 
SEATTLE SOUTHWARD. WEAK ONSHORE FLOW WILL RETURN MONDAY. HIGHS WILL 
COOL 10-15 DEGREES AT THE COAST AND THERE WILL LIKELY BE SOME 
MORNING LOW CLOUDS AND FOG FOR THE COAST AGAIN BUT THE INTERIOR OF 
WRN WA WILL REMAIN RATHER WARM.

.LONG TERM...THE WARMTH WILL CONTINUE THROUGH AT LEAST WEDNESDAY AS 
LOW LEVEL ONSHORE FLOW IS LIKELY TO REMAIN WEAK. A COOLING TREND 
SHOULD START THURSDAY AND FRIDAY AS AN UPPER TROUGH NEARS THE AREA. 
THE UPPER LOW THAT HAS BEEN OFF CALIF IS SHOWN SHIFTING OVER NRN 
CALIF THU AND FRI...WITH SHOWERS SPREADING ACROSS OREGON. THERE ARE 
ALSO SHOWERS SHOWN OVER B.C. ASSOCIATED WITH A NORTHERN UPPER TROUGH 
FRI AND SAT...BUT WRN WA IS MAINLY DRY.

&&

.AVIATION...STRONG HIGH PRESSURE REMAINS OFFSHORE WHILE AN UPPER 
LEVEL LOW SPINS OVER NORTHERN ALBERTA. THE FLOW ALOFT OVER WESTERN 
WA IS W/NW. THE AIR MASS IS DRY. SKIES ARE CLEAR EXCEPT FOR PATCHY 
LOW LEVEL STRATUS CLOUDS ALONG THE CENTRAL COAST...BUT THESE CLOUDS 
WILL ERODE LATE THIS MORNING. HIGH PRES AND OFFSHORE FLOW WILL KEEP 
SKIES CLEAR TONIGHT AND SUN FOR VFR CONDITIONS. 

KSEA...VFR CONDITIONS. LIGHT N WINDS AT THE SURFACE. 33

&&

.MARINE...NORTHERLY FLOW WILL PREVAIL OVER THE WATERS TODAY WITH 
SURFACE HIGH PRES OVER B.C. MODELS SHOW N/NW WINDS OF 15 TO 25 KT 
OVER THE OUTER COASTAL WATERS - A SMALL CRAFT ADVISORY IS IN EFFECT 
THROUGH NOON TODAY. 

OFFSHORE FLOW WILL DEVELOP TONIGHT AND SUN AS A THERMAL TROUGH OF 
LOW PRES FORMS ALONG THE COAST. THE FLOW WILL FLIP BACK TO ONSHORE 
MON AND TUE AS LOW PRES SHIFTS INLAND. 33

&&

.SEW WATCHES/WARNINGS/ADVISORIES... 

WA...A HEAT ADVISORY IS IN EFFECT UNTIL MIDNIGHT SUNDAY NIGHT FOR    
 PARTS OF THE PUGET SOUND REGION.   
                                   
PZ...SMALL CRAFT ADVISORY IN EFFECT FOR THE COASTAL WATERS FROM CAPE 
    FLATTERY TO CAPE SHOALWATER FROM 10 NM OUT TO 60 NM UNTIL NOON	 
TODAY.
    
&&

$$

WWW.WEATHER.GOV/SEATTLE

[ W WA | SW WA and W OR | SE WA and NE OR | NE WA and N ID ]

Southwestern Washington and Western Oregon


539 
FXUS66 KPQR 041611
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
912 AM PDT SAT JUL 4 2015

.SYNOPSIS...LITTLE CHANGE IN THE OVERALL WEATHER PATTERN IS EXPECTED 
THROUGH THE HOLIDAY WEEKEND AND INTO EARLY NEXT WEEK. A STRONG UPPER 
LEVEL RIDGE WILL REMAIN OVER THE REGION TO KEEP INLAND TEMPS WELL 
ABOVE NORMAL WITH CONTINUED DRY CONDITIONS. EARLY NEXT WEEK AN UPPER 
LEVEL LOW CUTTING OFF NEAR THE CENTRAL CALIFORNIA COAST MAY SPIN 
SOME MOISTURE UP TOWARD THE LANE COUNTY CASCADES FOR A CHANCE OF 
THUNDERSTORMS. SOME COOLING LOOKS POSSIBLE LATE IN THE WEEK AS THE 
UPPER LEVEL RIDGE GIVES WAY TO A WEAK LOW PRES CENTER ALOFT. 

&&

.SHORT TERM...THE UPPER LEVEL RIDGE ACROSS SOUTHERN OREGON IS 
EXPECTED TO REMAIN IN PLACE FOR THE NEXT FEW DAYS. INCREASED ONSHORE 
FLOW FRI EVENING LIKELY RESULTED IN A LITTLE COOLING TO THE AIR 
MASS...AS REFLECTED IN 12Z SLE SOUNDING H8 TEMP DOWN TO 19 DEG C 
THIS MORNING. THIS EXPECTED TO HELP TAKE A FEW DEGREES OFF THE HIGH 
TEMPS TODAY. OVERNIGHT CONVECTION OVER SW OREGON SPREAD SOME HIGH 
CLOUDS UP INTO THE SOUTHERN PART OF THE FORECAST AREA THIS 
MORNING...WHICH ALSO MAY HELP CUT A COUPLE OF DEGREES OFF THE HIGHS 
IN THE SOUTH TODAY. MARINE CLOUDS WERE RATHER LIMITED THIS 
MORNING...MAINLY INTO THE COASTAL RIVER VALLEYS. WITH THE LIGHT 
ONSHORE FLOW EXPECT MARINE CLOUDS TO BREAK UP RELATIVELY QUICKLY 
TODAY. 
 
REMAINDER OF SHORT TERM DISCUSSION UNCHANGED...TONIGHT SHOULD BE 
WARMER AGAIN WITH NEAR-RECORD HIGH MINIMUM TEMPS EXPECTED AGAIN SUN 
MORNING. HIGH PRESSURE BUILDING BEHIND THE BRITISH COLUMBIA COLD 
FRONT WILL LIKELY FURTHER WEAKEN ONSHORE GRADIENTS...SHOVING THERMAL 
LOW PRESSURE OFF THE WA/N OR COAST. THIS WILL LEAD TO ANOTHER VERY 
HOT DAY SUNDAY WITH LITTLE TO NO MARINE INFLUENCE EXCEPT FOR THE 
IMMEDIATE COAST. WITH 850 MB TEMPS REMAINING +20 TO +22 DEG C AND 
LITTLE TO NO MARINE INVERSION...TEMPS SHOULD APPROACH 100 DEGREES 
AGAIN FOR SOME OF OUR INLAND VALLEY LOCATIONS. 

WITH THERMAL LOW PRESSURE BEING SHOVED OFFSHORE AND AN OVERALL WEAK
SYNOPTIC FLOW PATTERN ODDS ARE GOOD THAT A SOUTHERLY WIND REVERSAL
WILL DEVELOP ALONG THE COAST LATER SUN/SUN NIGHT...AND THE 00Z NAM
AND 4KM WRF-ARW SHOW THIS. WITH 500 MB HEIGHTS REMAINING WELL INTO
THE 580S IT WILL BE DIFFICULT FOR EVEN A STRONG SOUTHERLY SURGE TO BE
DEEP ENOUGH TO BRING RELIEF FROM THE HEAT INTO THE WILLAMETTE VALLEY.
THE BEST CHANCE FOR THIS TO OCCUR SUN NIGHT/MON IS EUGENE...BUT IT
APPEARS UNLIKELY AT THIS POINT. OVERALL AIR MASS ALOFT CHANGES LITTLE
MONDAY...SO BARRING A DEEPER SOUTHWESTERLY MARINE PUSH THAN
EXPECTED...MONDAY LOOKS LIKE ANOTHER HOT ONE WITH TEMPS WELL INTO THE
90S INLAND. THOUGHT ABOUT EXTENDING THE HEAT ADVISORY INTO EARLY NEXT
WEEK...BUT DECIDED TO HOLD OFF TO GET A BETTER FEEL FOR THE IMPACT
THE SOUTHERLY SURGE WILL OR WILL NOT HAVE INLAND.

MEANWHILE A CUTOFF UPPER LOW WILL LINGER OFF THE CA COAST...BUT 00Z
GFS/ECMWF/GEM ALL SUGGEST IT WILL BE TOO FAR SOUTH THROUGH MONDAY TO
BRING THUNDER INTO OUR FORECAST AREA. THIS MAY CHANGE IF THE UPPER
LOW WOBBLES A LITTLE FURTHER NORTH THAN CURRENTLY EXPECTED.  WEAGLE
 
.LONG TERM...TUESDAY THROUGH FRIDAY...GFS AND ECMWF SHOW THE UPPER
COL REMAINING OVER OREGON TUE AND WED FOR CONTINUED HOT WEATHER. THIS
ALSO LEAVES THE S CASCADES OPEN INSTABILITY AND MOISTURE ALOFT
SNEAKING UP FROM THE S...SO WILL KEEP A SLIGHT CHANCE FOR DIURNAL
THUNDERSTORMS OVER THE LANE COUNTY CASCADES BOTH TUE AND WED. MODELS
AT THIS POINT ARE SUGGESTING SOME RELIEF TO THE EXTENDED HEAT WAVE
COMING LATER IN THE WEEK AS THE UPPER LOW CUTOFF OFF THE CA COAST
MOVES INLAND OVER CA POTENTIALLY BRINGING A DEEPER SW PUSH OF MARINE
AIR INLAND. MODELS INDICATE THE TROUGHINESS OVER THE WESTERN STATES
IS THEN REINFORCED FRI AS ANOTHER TROUGH MOVES IN OFF THE N PACIFIC
FOR EVEN COOLER AIR. WILL TREND TEMPS DOWNWARD A LITTLE MORE FOR THU
AND FRI GIVEN DECENT AGREEMENT IN MODELS WITH THIS TYPE OF
SOLUTION...BUT STILL HOLD SOME RESERVATIONS IN BUYING COMPLETELY INTO
THE CHANGE AS MODELS TEND TO STRUGGLE WITH CUTOFF LOWS ESP THIS FAR
INTO THE EXTENDED PERIOD. 

&&

.AVIATION...STABLE WESTERLY FLOW ALOFT CONTINUES. PATCHY IFR/MVFR
MARINE STRATUS ALONG THE COAST THIS MORNING SHOULD BE GONE BY NO
LATER THAN 18Z. THEN EXPECT VFR TO REMAIN AT THE COAST THROUGH
MUCH OF THIS EVENING. MVFR/IFR COASTAL STRATUS IS EXPECTED TO
REFORM BY AROUND 06Z. VFR WILL REMAIN IN CONTROL INLAND FOR THE
NEXT 24 HRS.

KPDX AND APPROACHES...VFR IN CONTROL FOR THE NEXT 24 HRS. PYLE

&&

.MARINE...HIGH PRES OVER THE NE PAC AND THERMAL LOW PRES INLAND
WILL CONTINUE TO PRODUCE BREEZY NORTHERLY WINDS OVER THE COASTAL
WATERS TODAY. THE STRONGER WINDS ARE FURTHER OFFSHORE BUT REMAIN
BELOW ADVISORY CRITERIA. THE THERMAL LOW PRES WILL MOVE WESTWARD
LATER TONIGHT AND SUNDAY...WEAKENING THE PRES GRADIENT OVER THE
WATERS. THE FCST MODELS ARE INDICATING THAT A SOUTHERLY WIND
REVERSAL WILL OCCUR SOMETIME SUN.

EXPECT PERIODS OF STEEP AND CHOPPY SEAS OVER THE OUTER WATERS TO
CONTINUE TODAY WITH COMBINED SEAS OF 6 TO 8 FT AND A DOMINANT
PERIOD AROUND 8 SECONDS. LOOKS LIKE HAZARDOUS SEA CONDITIONS WILL
PERSIST OVER THE NORTHERN OUTER ZONE TODAY PRIMARILY WEST OF ABOUT
30 NM. SEAS SHOULD GRADUALLY SUBSIDE LATER THIS WEEKEND AS WINDS
SLACKEN...REACHING AROUND 4 TO 5 FT BY EARLY NEXT WEEK. PYLE/26

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HEAT ADVISORY UNTIL 6 PM PDT SUNDAY FOR CASCADE FOOTHILLS IN 
     LANE COUNTY-CENTRAL COAST RANGE OF WESTERN OREGON-CENTRAL 
     COLUMBIA RIVER GORGE-CENTRAL WILLAMETTE VALLEY-GREATER 
     PORTLAND METRO AREA-LOWER COLUMBIA-NORTHERN OREGON CASCADE 
     FOOTHILLS-SOUTH WILLAMETTE VALLEY-UPPER HOOD RIVER VALLEY-
     WESTERN COLUMBIA RIVER GORGE.

WA...HEAT ADVISORY UNTIL 6 PM PDT SUNDAY FOR CENTRAL COLUMBIA RIVER 
     GORGE-GREATER VANCOUVER AREA-I-5 CORRIDOR IN COWLITZ COUNTY-
     SOUTH WASHINGTON CASCADE FOOTHILLS-WESTERN COLUMBIA RIVER 
     GORGE.

PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM PDT THIS 
     AFTERNOON FOR WATERS FROM CAPE SHOALWATER WA TO CASCADE 
     HEAD OR FROM 10 TO 60 NM.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA		
WWW.FACEBOOK.COM/NWSPORTLAND		
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON 
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS 
COMMONLY REFERRED TO AS THE FORECAST AREA.

[ W WA | SW WA and W OR | SE WA and NE OR | NE WA and N ID ]

Southeastern Washington and Northeastern Oregon


309 
FXUS66 KPDT 041610
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
908 AM PDT SAT JUL 4 2015

.SHORT TERM... FORECAST REMAINS ON TRACK WITH ONLY MINOR CHANGES TO 
MAINLY SKY COVER...TEMPERATURES AND WINDS. THERE ARE SOME SCT TO BKN 
HIGH CLOUDS ACROSS MUCH OF NORTH-CENTRAL OREGON THIS MORNING WHICH 
ARE FORECAST TO REMAIN GENERALLY IN PLACE THROUGH TODAY AND TONIGHT 
BEFORE SHIFTING SOUTH BY SUNDAY. THE CLOUDS THIN OUT AND ALLOW FOR 
MOSTLY SUNNY/CLEAR CONDITIONS TO PREVAIL HEADING NORTH TOWARD THE 
BLUE MOUNTAIN FOOTHILLS...COLUMBIA BASIN AND INTO 
WASHINGTON...OVERALL DID RAISE SKY COVER SLIGHTLY OVER MUCH OF 
OREGON TO ACCOUNT FOR THESE CLOUDS. OTHERWISE IT WILL BE ANOTHER HOT 
AFTERNOON ACROSS THE FORECAST AREA...AFTERNOON HIGHS WERE RAISED A 
DEGREE OR TWO WITH HIGHS EXPECTED TO RANGE FROM 98 TO 105 IN THE 
LOWER ELEVATIONS/BASINS AND IN THE 80S TO MID-90S FOR THE MOUNTAINS. 
IT WILL STAY DRY AND VERY MILD THIS EVENING INTO THE OVERNIGHT HOURS 
WITH LOW TEMPERATURES ONLY DIPPING DOWN INTO THE MID TO UPPER 60S IN 
THE COLUMBIA BASIN AND SURROUNDING VALLEYS WITH 50S IN THE 
MOUNTAINS. SUNDAY WILL REMAIN VERY WARM BUT LIKELY A FEW DEGREES 
COOLER THAN THIS AFTERNOON...WITH HIGH TEMPERATURES IN THE MID-90S 
TO AROUND 100 FOR THE LOWER ELEVATIONS. KEPT CONDITIONS DRY FOR NOW 
BUT WILL MAY NEED TO REEVALUATE THE THREAT FOR AT LEAST SOME 
ISOLATED PM THUNDERSTORMS ACROSS PARTS OF OUR OREGON MOUNTAIN ZONES 
WITH THE AFTERNOON GUIDANCE. 77
 
&&

.FIRE WEATHER...THE RED FLAG WARNINGS FOR WIND AND LOW RELATIVE 
HUMIDITY FOR PORTIONS OF THE COLUMBIA BASIN...EASTERN COLUMBIA RIVER 
GORGE...AND NORTH CENTRAL AND CENTRAL OREGON WILL CONTINUE TODAY.  
RH'S WILL BE SIMILAR TO YESTERDAY...I.E. 8 TO 15 PERCENT FOR MOST OF 
THE REGION.  WINDS MAY BE LESS THAN YESTERDAY BUT WILL STILL BRING 
THE POSSIBILITY OF RAPID FIRE SPREAD IN SOME AREAS WHERE WINDS WILL 
INCREASE TO AROUND 10-20 MPH THIS AFTERNOON AND EVENING.  THE 
WARNING FOR THE HANFORD DISTRICT AND THE YAKIMA VALLEY IS IN EFFECT 
THROUGH SUNDAY MORNING. NORTHERLY WINDS WILL INCREASE THERE TONIGHT 
AND GUSTS TO 30-35 MPH ARE POSSIBLE...MAINLY ALONG RATTLESNAKE 
RIDGE.  THE FIRE WEATHER CONCERNS WILL SHIFT TO THE THUNDERSTORM 
POTENTIAL LATER THIS WEEK...AND THIS WILL BE ADDRESSED IN FUTURE 
DISCUSSIONS.  WISTER

&&

.PREV DISCUSSION... /ISSUED 420 AM PDT SAT JUL 4 2015/ 

SHORT TERM...TODAY THROUGH MONDAY...AN UPPER RIDGE WILL CONTINUE 
TODAY SOUTHEAST OF THE FORECAST AREA OVER THE GREAT BASIN AND THERE 
WILL BE A NORTHWEST FLOW OVER THE CWA NORTH OF THE RIDGE. THIS WILL 
KEEP HIGH HEIGHTS AND VERY WARM 850 MB TEMPERATURES OVER THE REGION 
TODAY AND WILL RESULT IN ANOTHER HOT DAY FOR THE FORECAST AREA WITH 
HIGHS AROUND 100 IN THE LOWER ELEVATIONS AND 80S TO LOWER 90S IN THE 
MOUNTAINS. THESE TEMPERATURES HOWEVER DO NOT MEET HEAT ADVISORY 
CRITERIA. SURFACE PRESSURE GRADIENTS WILL TIGHTEN UP ALONG THE 
CASCADE EAST SLOPES THIS AFTERNOON. THIS WILL CAUSE INCREASING WINDS 
ALONG THE CASCADE EAST SLOPES AND ADJACENT VALLEYS AND PLATEAUS. 
THIS COMBINED WITH LOW RELATIVE HUMIDITY AND HOT TEMPERATURES WILL 
CONTINUE TO WARRANT RED FLAG WARNINGS FOR CRITICAL FIRE WEATHER 
CONDITIONS IN THE FIRE WEATHER ZONES JUST EAST OF THE CASCADES. 
ELSEWHERE WINDS WILL BE MOSTLY LIGHT TODAY. ON SUNDAY WINDS WILL 
REMAIN LIGHT IN ALL AREAS WHICH WILL REDUCE THE THREAT OF CRITICAL 
FIRE WEATHER CONDITIONS. RED FLAG WARNINGS WILL REMAIN IN EFFECT 
UNTIL 9 AM SUNDAY MORNING FOR PORTIONS OF THE WASHINGTON YAKIMA AND 
KITTITAS VALLEYS AND A PORTION OF THE LOWER COLUMBIA BASIN ADJACENT 
TO THESE VALLEYS. TEMPERATURES WILL BE ANOTHER COUPLE DEGREES COOLER 
ON SUNDAY. THE UPPER RIDGE SOUTHEAST OF THE CWA WILL NUDGE BACK TO 
THE NORTHWEST ON MONDAY RESULTING IN WARMING TEMPERATURES BY A 
DEGREE OR TWO...BUT NOT ENOUGH FOR A HEAT ADVISORY ANYWHERE IN THE 
CWA. TEMPERATURES WILL THEN REMAIN NEARLY STEADY GOING INTO THE 
EXTENDED FORECAST PERIOD. 88

LONG TERM...MONDAY NIGHT THROUGH FRIDAY NIGHT...UPPER LEVEL LOW OFF 
THE CALIFORNIA COAST WILL SLOWLY PROGRESS EASTWARD THROUGH THE LONG 
TERM PERIOD. AN UPPER LEVEL RIDGE WILL PERSIST TO THE SOUTHEAST. THE 
LOW WILL BRING MID LEVEL MOISTURE AND INSTABILITY TO SOUTHEASTERN 
OREGON. THIS MOISTURE AND INSTABILITY MAY BRING AFTERNOON AND 
EVENING THUNDERSTORMS TO THE SOUTHERN BORDER OF THE CWA FROM CENTRAL 
OREGON TO GRANT COUNTY. DRY WEST TO NORTHWEST FLOW WILL KEEP DRY 
CONDITIONS WITH MOSTLY CLEAR SKIES IN OTHER AREAS. BY THURSDAY 
COVERAGE WILL SPREAD TO NORTHEAST OREGON AS THE LOW MOVES INLAND AND 
UPPER LEVEL FLOW CHANGES TO SOUTHERLY OVER THE REST OF EASTERN 
OREGON AND WASHINGTON. AS THE LOW EXITS THE AREA FRIDAY 
NIGHT...EXPECT DRY WESTERLY FLOW TO SET IN AND PERHAPS AN INCREASE 
IN WINDS. GFS INDICATES MUCH COOLER AIR AND HIGHER SURFACE 
HUMIDITIES POSSIBLE WITH THIS WESTERLY FLOW.  COONFIELD

AVIATION...12Z TAFS...VFR CONDITIONS WILL OCCUR OVER THE NEXT 24 
HOURS WITH SCT CIRRUS OVER KBDN AND KRDM FROM THUNDERSTORM BLOWOFF 
AND INCREASING UPPER LEVEL MOISTURE BROUGHT IN FROM THE SOUTH. WINDS 
BTWN 5 TO 15 KTS WILL OCCUR OVERNIGHT TONIGHT BECOMING NORTHERLY 10 
TO 20 KTS AFT 04/21Z DUE TO PASSING SHORTWAVE TROUGH. 76

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT 100  65  97  64 /   0   0   0   0 
ALW 101  71  96  69 /   0   0   0   0 
PSC 104  68 100  66 /   0   0   0   0 
YKM 105  68  96  66 /   0   0   0   0 
HRI 103  66 100  65 /   0   0   0   0 
ELN 102  65  98  62 /   0   0   0   0 
RDM  97  57  95  57 /   0   0   0   0 
LGD  94  59  91  57 /   0   0   0   0 
GCD  99  59  97  57 /   0  10   0   0 
DLS 101  69 101  69 /   0   0   0   0 

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...RED FLAG WARNING UNTIL 8 PM PDT THIS EVENING FOR ORZ610-639>641.

WA...RED FLAG WARNING UNTIL 8 PM PDT THIS EVENING FOR WAZ639.

     RED FLAG WARNING UNTIL 9 AM PDT SUNDAY FOR WAZ675.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

77/76/93/85

[ W WA | SW WA and W OR | SE WA and NE OR | NE WA and N ID ]

Northeastern Washington and Northern Idaho


598 
FXUS66 KOTX 041127
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
427 AM PDT SAT JUL 4 2015

.SYNOPSIS....
Hot and dry weather will be featured for the Independence Day
weekend. Today winds will shift to the north and increase as a
front sags in from Canada. Breezy conditions continue on Sunday.
It is still looking dry and warm into the beginning of next week.



&&

.DISCUSSION...
Today through Sunday...A dry cold front will sag south across the
Inland Northwest later today, bringing increasing northerly winds
to the Okanogan Valley late this morning that will spill out into
the Waterville Plateau and western Columbia Basin by around noon.
Winds will continue to increase during the afternoon and early
evening hours with sustained winds of 15 to 25 mph and gusts to 35
mph. This will combine with very low relative humidity to produce
critical fire weather conditions. The Red Flag Warning remains in
effect for these areas, FWZ673, 684 and 687, through 10 pm. The
Northeast WA fire districts will see lighter winds during peak
daytime heating (and minimum RH) so the decision was made to not
expand the warning to FWZ686. It will still be hot and dry, but
winds will be less of a concern. There will be almost no
precipitation with this front so temperatures will remain hot.
Expect readings a few degrees cooler than Friday's numbers, which
will still be well above seasonal normals.

As the front pivots through the forecast area tonight, the focus
will shift to northeast Washington and the northern panhandle of
Idaho. There may even be an isolated thunderstorm or two for the
northern panhandle mountains early Sunday morning but confidence
is low. The winds continue to be the main concern. Northeast winds
will be channeled down the Purcell trench into the west plains.
Fortunately, the winds will be increasing during the overnight
hours while relative humidity is recovering. There is a low
probability of critical winds and low RH for Sunday afternoon but
for now it looks like RHs will recover a bit behind the front as
slightly cooler air arrives from the north. temperatures will cool
a bit with some of the northern valley locations in the 80s. We
will continue to re-evaluate expected fire weather conditions with
the next forecast package. /Kelch

Sunday night through Saturday...The models are in decent agreement
handling the current weather pattern(s). Deep low pressure
centers anchor the end points in the Gulf of Alaska and in the
vicinity of Hudson Bay. In between high pressure will build in the
eastern Pacific. This will put the Inland northwest in a northwest
to northerly flow through about Wednesday, depending on what model
you like. a weather disturbance moving through the northerly flow
will clip the northeast zones Tuesday and Tuesday night. Behind
that disturbance high pressure will build back into the Pac NW
through Thursday in response to the Gulf of Alaska low moving into
the eastern Pacific. By Friday night/Saturday the models are
hinting that the Gulf of Alaska low will move into position just
off the coast.

Sunday night to Monday night expect a slight rebound of the
temperatures and a continued dry forecast gusty winds from Sunday
will decrease and remain out of the northwest.

Tuesday and Tuesday night...increased moisture with the aforementioned
short wave will tap into both surface based and mid level
instability and result in a chance for showers and thunderstorms.
These storms will be focused along the northeast Washington
mountains and the north Idaho Panhandle. The convection should be
isolated at best, but any lightning after this extended period of
dry weather will result in potential fire starts. The remainder of
the region will remain dry with temperatures 8-12 degrees above
normal. Another thing we will need to keep an eye on will be
increased winds down the Okanogan valley Tuesday. At this time it
doesn't look like a strong front but winds will be on the
increase.

Wednesday and Thursday another transient ridge axis will track
across the area for a period of very warm and dry conditions.

Friday and Saturday things may get interesting. All of the model
guidance is indicating the upper low will move to just off the
Washington coast in some form or other. This is the a very good
pattern east of the Cascades for a convective outbreak as
southerly flow will tap into fairly deep sub-tropical moisture. If
this pattern verifies there will be a chance for thunderstorms
both Friday ad Saturday. Thunderstorms possibly starting off high
in the atmosphere for virga, little precipitation, and gusty
outflow winds on Friday and Friday night...then becoming much
wetter Saturday. Tobin

&&

.AVIATION... 
12Z TAFS: A dry airmass will allow for VFR conditions at all TAF
sites. Winds at KEAT will remain occasionally breezy through
this afternoon. Elevated smoke layers from area wildfires will
appear as thin mid level clouds but surface visibility will not be
affected. Northerly winds will pick up aft 00z along the Canadian
border and push south through the evening hours towards KGEG KCOE
and KMWH. /EK


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        98  67  89  61  91  67 /   0  10  10   0   0   0 
Coeur d'Alene  95  62  85  57  89  61 /   0  10  10   0   0   0 
Pullman        94  59  89  53  90  56 /   0   0  10   0   0   0 
Lewiston      103  71  98  65  98  68 /   0   0   0   0   0   0 
Colville      100  61  92  57  94  62 /   0  10  10   0   0  10 
Sandpoint      94  54  83  49  88  54 /   0  10  10   0   0  10 
Kellogg        94  61  83  52  88  57 /   0  10  10   0   0   0 
Moses Lake    102  71  97  66  98  68 /   0   0   0   0   0   0 
Wenatchee     103  75  98  72  99  72 /   0   0   0   0   0   0 
Omak          100  66  96  63  97  65 /   0   0   0   0   0  10 

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Red Flag Warning from Noon today to 10 PM PDT this evening for 
     East Washington Northern Columbia Basin (Zone 673)-East 
     Washington Okanogan Highlands (Zone 687)-East Washington 
     Okanogan/Methow Valleys (Zone 684).

&&

$$

[ W WA | SW WA and W OR | SE WA and NE OR | NE WA and N ID ]

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