Wildfire in Oregon, July 22 to 27, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
237 AM PDT FRI JUL 22 2005

.SHORT TERM...TODAY THROUGH SUNDAY. AN UPPER LEVEL TROUGH IS MOVING
INTO SW OREGON...TAKING A SLIGHT NEGATIVE TILT.  NUMEROUS LIGHTNING
STRIKES HAVE BEEN DETECTED OVER WESTERN OREGON...AND A FEW STORMS
HAVE DEVELOPED THIS MORNING IN CROOK COUNTY.  DOPPLER RADARS AT
PENDLETON AND SURROUNDING OFFICES ARE SHOWING LIGHT PRECIPITATION
WITH RAINFALL ESTIMATES ONLY A TRACE OVER MOST OF OUR FORECAST AREA
WITH A FEW PIXELS AROUND 0.05.  THE ONLY SURFACE OBSERVATION THAT
HAS MEASURED MORE THAN A TRACE HAS BEEN POWELL BUTTE RAWS WITH
0.01.  KEEPING THIS IN MIND...WILL CONTINUE THE RED FLAG WARNING
UNTIL 3 PM OVER MOST OF THE FORECAST AREA.  DETAILS ON THIS WARNING
CAN BE FOUND IN THE FIRE WEATHER SECTION OF THIS DISCUSSION.  ONE
THING TO NOTE IS THE PRECIPITABLE WATERS FROM SURROUNDING RAOB
SITES.  WHILE 00Z SOUNDINGS AT SALEM AND MEDFORD ARE AROUND 1.2
INCHES...SPOKANE SOUNDING IS ONLY SHOWING 0.39 INCH.  THIS IS A GOOD
INDICATOR THAT THE AIR MASS WILL GRADUALLY MOISTEN AS THE DAY
PROGRESSES.  WILL KEEP SCATTERED DRY TSTMS IN OUR EASTERN ZONES THIS
MORNING BUT WILL MENTION SCATTERED SHOWERS AND TSTMS FOR OUR WESTERN
ZONES WHICH COVERS THE EAST SLOPES OF THE CASCADES...THE EASTERN
COLUMBIA GORGE...CENTRAL AND NORTH CENTRAL OREGON...AND THE OCHOCO
MOUNTAINS.

THE LOW IS EXPECTED TO WEAKEN AS IT MOVES ACROSS OREGON AND EASTERN
WASHINGTON.  IT WILL MOVE INTO IDAHO AND MONTANA THIS EVENING.  A
DRY SW FLOW WILL FOLLOW THE SYSTEM.  WINDS BEHIND THE FRONT WILL
INCREASE THIS AFTERNOON AND EVENING AND WILL BE WINDY IN THE
KITTITAS VALLEY...THE EASTERN COLUMBIA GORGE...AND PORTIONS OF THE
COLUMBIA BASIN AND CASCADES VALLEYS.  WINDS WILL DIMINISH OVERNIGHT
AND SKIES WILL CLEAR.  DRY CONDITIONS AND LOCALLY BREEZY WINDS CAN
BE EXPECTED THE REMAINDER OF THE WEEKEND.  SMITH

.LONG TERM...HIGH PRESSURE ALOFT WILL DOMINATE THE WEATHER FOR MOST
OF THE EXTENDED PERIOD WITH CONTINUED VERY WARM AND DRY CONDITIONS.
THE UPPER RIDGE WILL BEGIN REBUILDING OVER THE REGION MONDAY NIGHT
AND WILL BECOME MOST AMPLIFIED ON WEDNESDAY AND THURSDAY. THESE WILL
BE THE TWO HOTTEST DAYS IN THE EXTENDED PERIOD WITH TEMPERATURE
READINGS IN THE UPPER 90S...POSSIBLY TOPPING OVER 100 IN THE LOWER
COLUMBIA BASIN AND BLUE MOUNTAIN FOOTHILLS. IN THE MOUNTAINS IT WILL
BE MOSTLY IN THE 80S TO LOWER 90S. THE NEW GFS RUN IS ADVERTISING AN
UPPER TROUGH WITH SOME MONSOON MOISTURE FROM THE SOUTH TO WORK ITS
WAY NORTHWARD INTO THE FORECAST AREA ON THURSDAY AS THE UPPER RIDGE
AXIS MOVES TO THE EAST AND ALLOWS THE FLOW ALOFT TO BECOME MORE
SOUTHERLY. BEING THAT THE MODELS USUALLY HAVE POOR RUN TO RUN
CONSISTENCY AND MODEL TO MODEL CONSISTENCY AT THIS RANGE (7 DAYS
OUT) WILL LEAVE FORECAST DRY FOR NOW AND JUST ADD SOME CLOUDS.
BEYOND THURSDAY HOT AND DRY CONDITIONS WILL CONTINUE AS ANOTHER
UPPER RIDGE BECOMES RE-ESTABLISHED OVER THE PACIFIC NORTHWEST ON
FRIDAY. 88

&&

.AVIATION...ISOLATED TO SCATTERED THUNDERSTORMS WILL CONTINUE EARLY
THIS MORNING...HOWEVER CONDITIONS WILL REMAIN VFR. WINDS WILL BE
GUSTY NEAR ANY SHOWERS OR THUNDERSTORMS WITH SPEEDS 20 TO 30 MPH
EXPECTED...OTHERWISE THE WINDS SHOULD BE LIGHT. CLEARING WILL BEGIN
FROM WEST TO EAST TODAY AS MORE STABLE AIR MOVES BACK INTO THE
REGION. 88

&&

.FIRE WEATHER...AS STATED IN THE SHORT-TERM DISCUSSION...THE RED
FLAG WARNING WILL BE EXTENDED UNTIL 3 PM THIS AFTERNOON.  ALTHOUGH
THE AIR MASS WILL MOISTEN AND A FEW THUNDERSTORMS MAY PRODUCE
WETTING RAIN (I.E. AMOUNTS GREATER THAN 0.1 OF AN INCH)...THE
FORECAST AREA HAS BEEN UNDER A DRY SPELL FOR A COUPLE OF WEEKS AND
THE AREAS UNDER THE WARNING HAVE GRASSES AND OTHER FINE FUELS WITH
VERY LOW MOISTURE.  SMITH

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  88  59  90  59 /  20   0   0   0
ALW  95  62  91  64 /  20   0   0   0
PSC  94  60  92  58 /  20   0   0   0
YKM  91  56  89  57 /  20   0   0   0
HRI  94  59  92  58 /  20   0   0   0
ELN  85  59  84  55 /  20   0   0   0
RDM  88  46  89  44 /  30   0   0   0
LGD  87  56  90  52 /  20   0   0   0
5J0  89  53  92  50 /  20   0   0   0
DLS  88  61  86  61 /  30   0   0   0

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...RED FLAG WARNING UNTIL 3 PM FRIDAY FOR ORZ041-ORZ042-ORZ043-
     ORZ044-ORZ045-ORZ046-ORZ047-ORZ048.

WA...RED FLAG WARNING UNTIL 3 PM FRIDAY FOR WAZ024-WAZ025-WAZ026-
     WAZ027-WAZ028-WAZ029.

&&

TI:YGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
85/88/88

HAZARDOUS WEATHER OUTLOOK...UPDATED THE DAY ONE DISCUSSION...
NATIONAL WEATHER SERVICE PENDLETON OR
1210 PM PDT THU JUL 21 2005

...CRITICAL FIRE WEATHER CONDITIONS THIS AFTERNOON AND TONIGHT...

WAZ024>030-ORZ041>050-221215-
EAST SLOPES OF THE SOUTHERN CASCADES-KITTITAS VALLEY-
YAKIMA VALLEY-LOWER COLUMBIA BASIN OF WASHINGTON-
FOOTHILLS OF THE BLUE MOUNTAINS OF WASHINGTON-
NORTHWEST BLUE MOUNTAINS-EASTERN COLUMBIA RIVER GORGE OF OREGON-
NORTH CENTRAL OREGON-CENTRAL OREGON-
LOWER COLUMBIA BASIN OF OREGON-
FOOTHILLS OF THE BLUE MOUNTAINS OF OREGON-BLUE MOUNTAINS-
JOHN DAY BASIN-OCHOCO-JOHN DAY HIGHLANDS-GRANDE RONDE VALLEY-
WALLOWA COUNTY-
1210 PM PDT THU JUL 21 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL AND NORTHEAST OREGON
AS WELL AS SOUTH CENTRAL AND SOUTHEAST WASHINGTON.

.DAY ONE...TODAY AND TONIGHT

...HIGH FIRE DANGER THIS AFTERNOON (FROM NOON TODAY TO 7 PM PDT)...
     EAST COLUMBIA RIVER GORGE OF WASHINGTON, EAST SLOPES OF THE
     SOUTHERN CASCADES, KITTITAS VALLEY, YAKIMA VALLEY, LOWER
     COLUMBIA BASIN OF WASHINGTON, FOOTHILLS OF THE BLUE MOUNTAINS
     OF WASHINGTON, EASTERN COLUMBIA RIVER GORGE OF OREGON, NORTH
     CENTRAL OREGON, CENTRAL OREGON, LOWER COLUMBIA BASIN OF
     OREGON, FOOTHILLS OF THE BLUE MOUNTAINS OF OREGON, BLUE
     MOUNTAINS, JOHN DAY BASIN, OCHOCO-JOHN DAY HIGHLANDS

A VERY DRY AIR MASS IS OVER EASTERN WASHINGTON AND EASTERN OREGON.
THE AIR MASS WILL BECOME MORE UNSTABLE AS THE DAY PROGRESSES.  THE
COMBINATION OF HOT...DRY AND UNSTABLE CONDITIONS WILL RESULT IN A
POTENTIAL FOR EXTREME FIRE BEHAVIOR AND THUS HIGH FIRE DANGER.
THEREFORE...ANY FIRE STARTS THIS AFTERNOON AND EARLY THIS EVENING
COULD GROW RAPIDLY INTO WILDFIRES...WHICH IN TURN COULD PRODUCE
TOWERING SMOKE COLUMNS. GLOWING EMBERS IN A SMOKE COLUMN CAN FALL
OUT DOWNWIND FROM THE SMOKE COLUMN AND LEAD TO SPOTTING AND THUS
ADDITIONAL FIRE STARTS DOWNWIND FROM THE MAIN FIRE. A RED FLAG
WARNING IS IN EFFECT FROM NOON TO 7 PM PDT FOR THE YAKIMA
VALLEY...THE LOWER COLUMBIA BASIN...THE BLUE MOUNTAIN FOOTHILLS...
JOHN DAY BASIN...THE OCHOCO-JOHN DAY HIGHLANDS...AND PORTIONS OF
CENTRAL AND NORTH CENTRAL OREGON.

...THUNDERSTORMS WITH DRY LIGHTNING FROM 2 PM PDT THIS AFTERNOON
TO 5 AM PDT FRIDAY...
     EAST SLOPES OF THE SOUTHERN CASCADES, KITTITAS VALLEY,
     FOOTHILLS OF THE BLUE MOUNTAINS OF WASHINGTON, NORTHWEST BLUE
     MOUNTAINS, FOOTHILLS OF THE BLUE MOUNTAINS OF OREGON, BLUE
     MOUNTAINS, OCHOCO-JOHN DAY HIGHLANDS, GRANDE RONDE VALLEY,
     WALLOWA COUNTY

THUNDERSTORMS WILL THREATEN EASTERN OREGON AND EASTERN WASHINGTON
TONIGHT. VERY LITTLE...IF ANY...MEASURABLE RAINFALL CAN BE EXPECTED
WITH THESE THUNDERSTORMS. GUSTY AND ERRATIC WINDS ARE ALSO EXPECTED
WITH THUNDERSTORMS TONIGHT WITH WIND GUSTS UP TO 50 MPH POSSIBLE. A
RED FLAG WARNING DUE TO DRY LIGHTNING AND THUNDERSTORMS AFTER AN
EXTENDED PERIOD OF DRY CONDITIONS IS IN EFFECT FROM NOON TODAY
THROUGH 5 AM FRIDAY FOR THE EAST SLOPES OF THE OREGON AND SOUTHERN
WASHINGTON CASCADES AND THE EASTERN COLUMBIA GORGE...AND FROM 7 PM
TONIGHT THROUGH 5 AM FRIDAY FOR CENTRAL... NORTH CENTRAL AND
NORTHEAST OREGON AS WELL AS SOUTH CENTRAL AND SOUTHEAST WASHINGTON.

THIS WILL BE THE FIRST LIGHTNING EVENT TO OCCUR AFTER A PROLONGED
DRY PERIOD COMBINED WITH THUNDERSTORMS PRODUCING VERY LITTLE...IF
ANY...MEASURABLE RAINFALL. AS SUCH...THESE FACTORS WILL CREATE
CRITICAL FIRE WEATHER CONDITIONS FOR ANY FIRE STARTS GENERATED BY
LIGHTNING STRIKES.

REFER TO THE LATEST RED FLAG WARNINGS IN PRODUCT PDXRFWPDT WMO
HEADER: WWUS86 KPDT FOR DETAILS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THUNDERSTORMS FRIDAY
     EAST COLUMBIA RIVER GORGE OF WASHINGTON, EAST SLOPES OF THE
     SOUTHERN CASCADES, KITTITAS VALLEY, YAKIMA VALLEY, LOWER
     COLUMBIA BASIN OF WASHINGTON, FOOTHILLS OF THE BLUE MOUNTAINS
     OF WASHINGTON, NORTHWEST BLUE MOUNTAINS, EASTERN COLUMBIA
     RIVER GORGE OF OREGON, NORTH CENTRAL OREGON, CENTRAL OREGON,
     LOWER COLUMBIA BASIN OF OREGON, FOOTHILLS OF THE BLUE
     MOUNTAINS OF OREGON, BLUE MOUNTAINS, JOHN DAY BASIN,
     OCHOCO-JOHN DAY HIGHLANDS, GRANDE RONDE VALLEY, WALLOWA COUNTY

THE LOW PRESSURE SYSTEM RESPONSIBLE FOR THE THUNDERSTORMS TONIGHT
WILL EXIT THE REGION ON FRIDAY.  A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS IS FORECAST FOR ALL OF THE FORECAST AREA FRIDAY
MORNING.  MOST THUNDERSTORMS WILL PRODUCE LIGHT TO MODERATE RAIN
FRIDAY MORNING.  DRY CONDITIONS ARE EXPECTED THE REMAINDER OF THE
PERIOD.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON FOR ISOLATED DRY
THUNDERSTORMS IN CENTRAL OREGON PRODUCING LIGHTNING STRIKES LEADING
TO FIRE STARTS.

SPOTTER ACTIVATION WILL BE LIKELY TONIGHT FOR SCATTERED DRY
THUNDERSTORMS IN CENTRAL AND ISOLATED DRY THUNDERSTORMS ELSEWHERE.

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

PROTOTYPE GRAPHICAL FORECASTS OF WEATHER HAZARDS OUT TO SEVEN DAYS
ARE DISPLAYED ON THE WORLD WIDE WEB AT:

WEATHER.GOV/PENDLETON

AND SELECT GRAPHICAL HAZARDS.