299
FXUS66 KPDT 171753
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
1053 AM PDT THU SEP 17 2026
KEY MESSAGES
- |ISOLATED TO SCATTERED THUNDERSTORM CHANCES (15-30% CHANCES)
ALONG THE BLUE MOUNTAINS AND ALONG THE FOOTHILLS OF THE BLUES
THROUGH FRIDAY.
- SLIGHT WARMING TREND, WITH HIGH TEMPERATURES CLIMBING INTO THE
MID TO UPPER 80S THROUGH THE WEEKEND.
- BREEZY WINDS ALONG THE COLUMBIA BASIN FRIDAY, BUT WILL SIT
WELL BELOW WIND ADVISORY CRITERIA (70-80% CHANCE).
DISCUSSION
CURRENT RADAR AND SATELLITE IMAGES ADVERTISE CLEAR/HIGH SKY DECK
WITH DRY CONDITIONS IN MOST OF THE AREA. AN AREA OF MID-LEVEL
MOISTURE COUPLED WITH LOW RADAR RETURNS IS LOCATED ACROSS
CENTRAL OREGON NEAR BEND AND REDMOND. THIS IS A RESULT OF A
CUT-OFF LOW PRESSURE SYSTEM WITH THE CENTER OVER THE
CALIFORNIA/OREGON BORDER. THIS SYSTEM WILL BE THE DRIVE FOR OUR
WEATHER OVER THE NEXT COUPLE OF DAYS, BRINGING RAIN SHOWERS
ACROSS THE CENTRAL OREGON THROUGH WALLOWA'S REGION (50-70%
CHANCES) WITH ISOLATED TO SCATTERED THUNDERSTORM DEVELOPMENT
OCCURRING (15-30% CHANCES) OVER THE NEXT 24 HOURS. AS THE LOW
PROGRESSES EASTWARD, 250-500 J/KG OF CAPE WILL DEVELOP, ALLOWING
SOME STORMS TO BE PULSING AND BRIEF, WITH NO ANTICIPATED SEVERE
WEATHER CONDITIONS EXPECTED (>90% CONFIDENCE). THE PRIMARY
CONCERNS WITH ANY DEVELOPING STORM THROUGH FRIDAY WILL BE
FREQUENT LIGHTNING, GUSTY OUTFLOWS, AND SMALL HAIL. THE
THUNDERSTORM THREAT WILL PAUSE GOING INTO FRIDAY MORNING, WITH A
SECONDARY PEAK GOING INTO FRIDAY AFTERNOON DURING PEAK HEATING
HOURS. DEVELOPMENT WILL BE MOSTLY CONFINED TO THE WALLOWAS AND
PARTS OF GRANT COUNTY HEADING INTO THE LATE FRIDAY AFTERNOON
TIME FRAME. AFTERWARDS, GUIDANCE IS IN GOOD AGREEMENT WE'LL HAVE
RIDGING TAKING OVER THE PATTERN THAT WILL TRANSITION US INTO A
DRIER PATTERN THROUGH AT LEAST THE BEGINNING OF NEXT WEEK
(70-80% CHANCE).
WITH THE ONSHORE OF THE RIDGE INTO NEXT WEEK, A SLIGHT WARMING
TREND BRINGING HIGH TEMPERATURES INTO THE MID TO UPPER 80S WILL
OCCUR THROUGH THE WEEKEND. AS A RESULT, WE MAY SEE ELEVATED FIRE
WEATHER CONDITIONS RE-DEVELOP WITH MIN RH'S DROPPING TO THE
20-30% RANGE ACROSS MOST OF THE REGION. I DON'T SEE CRITICAL
FIRE WEATHER CONDITIONS DEVELOPING AS WINDS WILL BE BELOW
CRITERIA THANKS TO THE UPPER LEVEL RIDGE BRINGING MOSTLY LIGHT
WINDS.
AVIATION /18Z TAFS THROUGH 18Z FRIDAY/
VFR CONDITIONS ARE
EXPECTED DURING THIS TAF PERIOD AT ALL SITES. LIGHT-MODERATE
RAIN SHOWERS ARE PRESENT AT SITES IN THE COLUMBIA BASIN
(PDT/ALW/PSC), ALONG THE BLUE MOUNTAIN AREA AND JOHN DAY
HIGHLANDS (RDM/BDN). CLEAR CONDITIONS ARE PRESENT AT DLS/YKM
WITH JUST A FEW SCATTERED CLOUDS. SHOWERS ARE MOVING ROUGHLY
NORTH-NORTHWEST AND WILL LIKELY PERSIST INTO THE AFTERNOON
HOURS (50% CONFIDENCE). OTHERWISE, WINDS WILL GENERALLY BE LIGHT
WITH SUSTAINED WINDS FROM 5-10 MPH. AMES/01
PRELIMINARY POINT TEMPS/POPS
PDT 71 50 77 47 / 40 60 0 0
ALW 72 55 78 54 / 40 60 0 0
PSC 78 52 81 51 / 10 10 0 0
YKM 79 52 81 52 / 0 0 0 0
HRI 75 53 81 51 / 20 40 0 0
ELN 77 51 77 50 / 0 0 0 0
RDM 65 41 75 40 / 70 50 0 0
LGD 72 48 74 46 / 80 60 10 10
GCD 69 48 74 46 / 70 60 10 10
DLS 84 57 82 54 / 0 0 0 0
PDT WATCHES/WARNINGS/ADVISORIES
WA...NONE.
OR...NONE.
UPDATE...99
DISCUSSION...95
AVIATION...01
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page