textproduct: Pendleton

KEY MESSAGES

- Widespread rain is likely overnight into Sunday.Areas in the flood watch should have many way to get alerts.

- Wind gusts above 30MPH are likely much of Sunday morning.

DISCUSSION

A low pressure system currently located off the coast of Oregon and Washington is moving south eastward, it should move ashore during the afternoon. After moving inland the low should begin steering towards the northeast. Rain should begin to develop as it moves inland. Overnight the rain will become more widespread.

Ensemble and deterministic gudience still remains in disagreement on QPF totals. Holistically the CWA should see an above normal amount of rain this time of year with EFI values between .8 and .9 and SOT of 2 and 1 on the Oregon/Washington border, putting emphasis on a potential for a high QPF rain event. Overall the QPF has decreased over the last several runs and reseeded more north toward our neighboring CWAs. NBM 10th percentile has the Kittitas valley receiving 1" of rain and the Colombia Basin and the Blue Mountains mostly receiving .20". The southern leeward side of the Cascades will likely be rain shadowed out of higher QPF totals. The 90th percentile QPF again Has the Kittitas Valley in higher QPF values and the Columbia Basin exceeding 1.20". Probabilities of >= .50" occurring excluding those along southern leeward side of the Cascades which will again be rain shadowed. >= 1" is where the Probs really decline throughout most of the area, aside from the Kittitas and Yakima Valley which remain >=80% chance.

Thunderstorms remain at <= 20% chance mostly occurring in the higher elevations of the Blue Mountains overnight. A potential exists for flooding over the Paradise and Hagen fires subsequent flood watches have been issued for those areas.

Wind gusts probs through much of Columbia Gorge, Basin, Kittitas Valley and Foothills of the Blue Mountains have a >90% chance of 35mph or greater. Most of the CWA should see at least 20-30 with those areas mentioned seeing higher gusts.

Temperatures over the weekend remain well below seasonal averages. Sundays high temperatures will remain in the 60-65F with cooler temperatures in the higher elevations. After sunday and through out the week temperatures will rebound to climate norms.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

The main concerns through the TAF period will be elevated winds, lower CIGs, and showers. Currently, VFR conditions are present at the TAF sites, but lower CIGs to MVFR are forecast at several terminals by around 10-12Z or so. CIGs will then fluctuate somewhat between MVFR and VFR through the day on Sunday (especially during periods of heavier showers). As for winds, expect sustained west southwest winds between 10-20 knots and gusts to between 20-35 tonight through Sunday afternoon. Shower chances also increase this evening, with medium to high chances persisting at times through Sunday afternoon before tapering off Sunday evening.

Preliminary Point Temps/PoPs

PDT 46 63 44 70 / 100 70 40 0 ALW 51 63 50 71 / 100 80 70 0 PSC 48 64 46 73 / 90 80 30 0 YKM 50 62 45 68 / 100 100 10 0 HRI 47 65 46 73 / 100 60 30 0 ELN 44 57 41 66 / 100 100 20 0 RDM 36 61 33 71 / 90 10 0 0 LGD 45 62 43 70 / 90 60 60 0 GCD 44 61 40 70 / 90 40 10 0 DLS 52 66 51 74 / 100 60 10 0

PDT WATCHES/WARNINGS/ADVISORIES

WA...Flash Flood Watch through Sunday evening for WAZ030. OR...Flash Flood Watch through Sunday evening for ORZ502.