702
FXUS66 KPDT 051800
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
1100 AM PDT SUN JUL 5 2026
KEY MESSAGES
- WARMING TEMPERATURES THROUGH TUESDAY.
- ISOLATED THUNDERSTORM CHANCES IN CENTRAL OREGON MOUNTAINS
TODAY, LOW THUNDERSTORM CHANCES (20 PERCENT OR LESS IN CENTRAL
OREGON MONDAY, SHIFTING TO EASTERN OREGON MOUNTAINS ON
TUESDAY.
- ELEVATED TO CRITICAL FIRE WEATHER CONDITIONS REDEVELOPING FROM
TUESDAY ONWARD.
DISCUSSION
ZONAL FLOW ACROSS THE AREA WILL BECOME MORE SOUTHWESTERLY BY
MONDAY. SEVERAL SHORT WAVES MOVING THROUGH THE FLOW WILL BRING
SHOWER AND THUNDERSTORM CHANCES MAINLY TO THE MOUNTAINS OF
CENTRAL AND EASTERN OREGON.
THUNDERSTORM CHANCES TODAY WILL BE VERY LOW (<15 PERCENT) AND
CONFINED TO THE MOUNTAINS OF CENTRAL OREGON. THE BEST (ALBEIT
LOW) CHANCES LOOK TO BE ON MONDAY AND OVER THE MOUNTAINS OF
CENTRAL OREGON, WITH CHANCES 20 PERCENT OR LESS. BY TUESDAY THE
THREAT MOVES MORE INTO EASTERN OREGON.
BY LATER TUESDAY, AN UPPER TROUGH AND COLD FRONT WILL APPROACH
THE REGION, AND MOVE THROUGH EARLY WEDNESDAY. WINDS WILL
INCREASE AHEAD OF THE TROUGH/FRONT. BY THURSDAY THROUGH FRIDAY,
WE ARE BACK IN A MORE ZONAL FLOW. BY THE WEEKEND THE FLOW TURNS
SOUTHWEST AGAIN AS A LARGE RIDGE BEGINS TO BUILD IN FROM THE
FOUR CORNERS AREA. EXACTLY HOW STRONGLY THIS RIDGE BUILDS IN
WILL HAVE A BIG IMPACT ON OUR TEMPERATURES AND GUIDANCE HAS NOT
BEEN CONSISTENT ON THE HANDLING OF THE RIDGE.
IN THE MEANTIME, TEMPERATURES WILL WARM THROUGH TUESDAY, WITH
TUESDAY BEING THE HOTTEST DAY IN ADVANCE OF THE APPROACHING
TROUGH/FRONT. HIGH TEMPERATURES ON TUESDAY WILL BE INTO THE 90S
IN MOST LOCATIONS WITH HIGHS IN THE COLUMBIA BASIN/YAKIMA VALLEY
BEING CLOSE TO 100 DEGREES IF NOT EXCEEDING 100 DEGREES. ON
WEDNESDAY, THE TROUGH/COLD FRONT WILL MOVE ACROSS THE AREA AND
TEMPERATURES WILL DECREASE BY ABOUT 5 TO 10 DEGREES.
AVIATION /18Z TAFS THROUGH 18Z MONDAY/
VFR CONDITIONS ARE FORECAST AT ALL SITES THROUGH THE PERIOD.
WINDS WILL BE DIURNALLY AND TERRAIN-DRIVEN, PREDOMINANTLY
SUSTAINED AT 10 KTS OR LESS WITH PERIODIC HIGHER GUSTS DURING
THE AFTERNOON AND EVENING. THERE IS A VERY LOW CHANCE (5-10
PERCENT) OF SHOWERS AND THUNDERSTORMS IN THE VICINITY OF BDN/RDM
LATER THIS AFTERNOON, WITH THOSE LOW CHANCES OF SHOWERS
CONTINUING THROUGH THE NIGHT; MOST LIKELY, ACTIVITY WILL REMAIN
TO THE SOUTH AND EAST.
FIRE WEATHER
A TROUGH AND COLD FRONT WILL APPROACH THE AREA ON TUESDAY, WITH
THE COLD FRONT MOVING THROUGH EARLY WEDNESDAY, WINDS WILL
INCREASE IN ADVANCE OF THE FRONT. THE FLOW WILL BECOME MORE
ZONAL BEHIND THE TROUGH/FRONTAL PASSAGE AND WINDS ARE GUSTY
WINDS ARE EXPECTED TO CONTINUE. ZONAL FLOW IS EXPECTED AGAIN ON
THURSDAY, BEFORE A MORE SOUTHWESTERLY FLOW DEVELOPS ON FRIDAY.
BREEZY TO WINDY CONDITIONS ARE EXPECTED ON TUESDAY INTO
WEDNESDAY, ESPECIALLY ACROSS THE CASCADE GAPS, SIMCOE HIGHLANDS,
KITTITAS VALLEY AN THE OREGON BASIN AND GORGE. WIND GUSTS LOOK
TO BE 25 TO 35 MPH, AND POSSIBLY AS HIGH AS 40 MPH. PROBABILITIES
OF WIND GUSTS OF >=25 ARE GREATER THAN 90 PERCENT. PROBABILITIES
OF WIND GUSTS >=39 MPH ARE 50 TO 80 PERCENT IN MANY OF THE
ABOVE LOCATIONS AND 90 PERCENT IN THE KITTITAS VALLEY.
WIND GUSTS LOOK TO BE LOWER ON THURSDAY BEFORE RAMPING UP AGAIN
ON FRIDAY. WIND GUSTS ON FRIDAY IN THESE SAME AREAS LOOK TO BE
25 TO 35 MPH. PROBABILITIES OF WIND GUSTS >=25 MPH ARE GREATER
THAN 90 PERCENT. PROBABILITIES OF WIND GUSTS >= 39 MPH ARE LOWER
THOUGH, ONLY ABOUT 30 TO 60 PERCENT, ON AVERAGE.
THESE WINDS COUPLED WITH RH VALUES MAINLY IN THE TEENS WILL
LEAD TO ELEVATED TO CRITICAL FIRE WEATHER CONDITIONS FROM
TUESDAY ONWARD. RH VALUES DO LOOK SLIGHTLY HIGHER ON WEDNESDAY,
BUT THE STRONGER WINDS COULD END UP NEGATING THAT. THURSDAY'S
LESSER WINDS COULD END UP HELPING THERE, BUT WILL HAVE TO SEE
HOW THE GUSTY WINDS AND LOW RH VALUES FIT TOGETHER AS THE WEEK
PROGRESSES.
PRELIMINARY POINT TEMPS/POPS
PDT 87 55 90 57 / 0 0 0 0
ALW 87 58 91 62 / 0 0 0 0
PSC 89 56 94 58 / 0 0 0 0
YKM 89 58 95 61 / 0 0 0 0
HRI 89 56 93 60 / 0 0 0 0
ELN 84 54 92 59 / 0 0 0 0
RDM 86 53 90 53 / 0 0 10 10
LGD 85 54 88 56 / 0 0 10 0
GCD 91 55 89 54 / 0 10 30 20
DLS 90 60 96 62 / 0 0 0 0
PDT WATCHES/WARNINGS/ADVISORIES
WA...NONE.
OR...NONE.
DISCUSSION...77
AVIATION...86
FIRE WEATHER...77
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