343
FXUS66 KPDT 130526
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
1026 PM PDT FRI JUN 12 2026
KEY MESSAGES
- WARMING AND DRYING TREND EXTENDS INTO NEXT WEEK.
- BREEZY WEEKEND WINDS WILL INCREASE EARLY NEXT WEEK.
- WINDY AND DRY CONDITIONS ELEVATE FIRE WEATHER CONCERNS.
DISCUSSION
CURRENT RADAR AND VISIBLE SATELLITE IMAGERY SHOWS DRY CONDITIONS
UNDER CLEAR SKIES. THIS IS IN RESPONSE TO AN UPPER LEVEL HIGH
PRESSURE SYSTEM THAT IS STRENGTHENING OFFSHORE TODAY BEFORE
SLOWLY MOVING ONSHORE LATE SATURDAY AND CROSSING THROUGH THE
PACIFIC NORTHWEST ON SUNDAY. A WARMING TREND WILL ENSUE AS THE
WARM AND DRY AIRMASS ASSOCIATED WITH THE HIGH PRESSURE RIDGE
MOVES OVER THE AREA. HIGH TEMPERATURES WILL REACH INTO THE LOW
TO MID-80S TODAY, MIDDLE TO UPPER 80S SATURDAY, LOW 90S SUNDAY,
AND INTO THE MIDDLE TO UPPER 90S MONDAY AND TUESDAY ACROSS
LOWER ELEVATIONS OF THE COLUMBIA BASIN, BLUE MOUNTAIN FOOTHILLS,
COLUMBIA GORGE, AND CENTRAL OREGON. HIGH TEMPERATURES MONDAY
AND TUESDAY ARE ABOUT 15 DEGREES ABOVE NORMAL FOR THIS TIME OF
YEAR. OVERNIGHT RELIEF WILL BE MINIMAL AS MORNING LOWS MONDAY
AND TUESDAY WILL ONLY DIP INTO THE LOWER TO MIDDLE 60S ACROSS
LOWER ELEVATIONS OF THE COLUMBIA BASIN, BLUE MOUNTAIN FOOTHILLS,
COLUMBIA GORGE, AND THE YAKIMA VALLEY. AS A RESULT, WIDESPREAD
MODERATE (2 OF 4) HEATRISK IS EXPECTED MONDAY, WITH ISOLATED
AREAS ON SUNDAY AND TUESDAY. PROBABILISTIC HEATRISK SUGGESTS AN
80-100% CHANCE OF MODERATE HEATRISK BEING REACHED ON MONDAY
ACROSS THESE AREAS, WITH SOME AREAS ALONG THE GORGE, TRI-CITIES,
AND YAKIMA INCLUDED IN A 40-60% CHANCE OF MAJOR (3 OF 4)
HEATRISK. THERE ARE SOME MODEL INCONSISTENCIES WITH THE STRENGTH
AND TIMING OF THE RIDGE WITH 45% OF MEMBERS SUGGESTING A WEAKER
OR LATER RIDGE PROGRESSION ONSHORE. HOWEVER, THESE DIFFERENCES
ARE RATHER MINOR, AND SHOULD ONLY RESULT IN TEMPERATURE
DIFFERENCES OF 2-4 DEGREES. AS CONFIDENCE GROWS, SO DOES THE
POTENTIAL FOR HEAT PRODUCTS BEING ISSUED AS EITHER AN ADVISORY
OR WARNING. AT THIS TIME, AN ADVISORY IS PROBABLE (50-70%)
MONDAY ACROSS THE COLUMBIA GORGE, YAKIMA VALLEY, AND CENTRAL
OREGON, DEPENDING ON THE INTRODUCTION OF CAMS GUIDANCE OVER THE
NEXT 24 HOURS.
THE RIDGE SLIDES ONSHORE OVER THE WEEKEND AND SUPPRESSES ON
MONDAY DUE TO AN INCOMING UPPER LEVEL TROUGH FROM THE NORTHWEST.
THE PRESSURE GRADIENT WILL TIGHTEN BETWEEN THESE TWO SYNOPTIC
FEATURES LATE MONDAY AND TUESDAY, ENHANCING WINDS ACROSS THE
AREA. THE STRONGEST WINDS ARE EXPECTED TO OCCUR BETWEEN TUESDAY
AFTERNOON THROUGH WEDNESDAY MORNING AS GUSTS UP TO 65 MPH WILL
BE POSSIBLE THROUGH THE KITTITAS VALLEY, AND UP TO 55 MPH OVER
THE SIMCOE HIGHLANDS, COLUMBIA GORGE, NORTH-CENTRAL OREGON, AND
THE BLUE MOUNTAIN FOOTHILLS. THE NBM ADVERTISES A 30-50% CHANCE
OF HIGH WIND WARNING LEVEL WIND GUSTS (>58+ MPH) THROUGH THE
KITTITAS VALLEY AND A 50-70% CHANCE OF ADVISORY-LEVEL (>45+ MPH)
WIND GUSTS OVER THE REMAINING AREAS OF THE COLUMBIA GORGE,
SIMCOE HIGHLANDS, AND THE BLUE MOUNTAIN FOOTHILLS. THE
UNCERTAINTIES IN TIMING AND STRENGTH OF THE INCOMING TROUGH AND
ATTENDANT COLD FRONT ALSO RELATE TO CONFIDENCE IN THESE WIND
VALUES, WITH 25% OF MEMBERS HIGHLIGHTING HIGHER WINDS THAN THE
CURRENT FORECAST AND 30% OF MEMBERS SWINGING IN THE OTHER
DIRECTION OF WEAKER WINDS. THIS WILL HAVE TO BE ANALYZED FURTHER
AS THE EVENT NEARS AND DETAILS FROM SHORT-TERM GUIDANCE CAN BE
ASSESSED.
THE COMBINATION OF WARM TEMPERATURES, DRY CONDITIONS, AND HIGH
WINDS PROVIDE ELEVATED FIRE WEATHER CONCERNS THAT PEAK ON
TUESDAY. EVEN THOUGH AFTERNOON HUMIDITY VALUES HOVER IN THE
LOWER TO MIDDLE TEENS THROUGH MONDAY, THE LACK OF ENHANCED
WINDS COINCIDING WITH THESE VALUES SUPPRESSES FIRE WEATHER
CONCERNS. HOWEVER, THE PASSING OF A COLD FRONT TUESDAY WILL
BRING WINDY CONDITIONS, MODERATE (30-50%) OVERNIGHT HUMIDITY
RECOVERIES, AND AFTERNOON HUMIDITIES IN THE MIDDLE TO UPPER
TEENS ACROSS SOME ZONES THAT HAVE RECEPTIVE FUELS. THESE WOULD
INCLUDE AREAS OF CENTRAL OREGON AND THE LOWER COLUMBIA BASIN.
TIMING LOOKS TO BE MOST OF THE DAY ON TUESDAY AFTER MIDDLE TO
LATE MORNING. STAY TUNED.
AVIATION /06Z TAFS THROUGH 06Z SUNDAY/
VFR CONDITIONS ARE FORECAST AT ALL SITES FOR THE NEXT 24 HOURS.
WINDS WILL BE DIURNALLY DRIVEN, PERIODICALLY BREEZY AND/OR
GUSTY DURING THE AFTERNOON AND EVENING HOURS WITH LIGHTER WINDS
OVERNIGHT. SKIES WILL BE CLEAR TO MOSTLY CLEAR.
FIRE WEATHER
AS STATED IN THE PRIMARY FORECAST DISCUSSION, FIRE WEATHER
CONCERNS PEAK TUESDAY ACROSS MUCH OF THE COLUMBIA BASIN
(WA/OR691) AND CENTRAL OREGON (OR700, OR704, AND OR705). THESE
ZONES ENCOMPASS ALL CURRENTLY DECLARED FIRE WEATHER ZONES, AS
FUELS WITHIN THESE ZONES HAVE BEEN FOUND TO BE RECEPTIVE TO
CARRY AND SPREAD FIRE. THERE ARE ISOLATED POCKETS OF FIRE
WEATHER CONCERNS OVER THE WEEKEND AND EVEN INTO MONDAY,
PRIMARILY RELATED TO AREAS OF NORTH-CENTRAL OREGON (OR703) AND
SOUTHERN BLUE MOUNTAINS/FOOTHILLS, (SW OR691) MIDDLE TO LATE
AFTERNOON. THE PASSING OF A COLD FRONT ON TUESDAY WILL ALSO LEAD
TO AN INCREASE IN INSTABILITY AND SHIFTING WIND DIRECTIONS
ALONG THE FRONTAL BOUNDARY. THIS MAY WARRANT A FIRE WEATHER
WATCH BEING ISSUED IN THE NEXT 24-48 HOURS RELATED TO TUESDAY'S
EVENT (50-60% CONFIDENCE). 75
PRELIMINARY POINT TEMPS/POPS
PDT 48 84 50 87 / 0 0 0 0
ALW 53 85 54 88 / 0 0 0 0
PSC 53 88 56 92 / 0 0 0 0
YKM 53 87 57 92 / 0 0 0 0
HRI 51 87 55 90 / 0 0 0 0
ELN 49 83 54 88 / 0 0 0 0
RDM 44 84 48 87 / 0 0 0 0
LGD 45 81 48 84 / 0 0 0 0
GCD 43 83 45 87 / 0 0 0 0
DLS 56 90 62 93 / 0 0 0 0
PDT WATCHES/WARNINGS/ADVISORIES
WA...NONE.
OR...NONE.
DISCUSSION...75
AVIATION...86
FIRE WEATHER...75
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