textproduct: Pendleton

KEY MESSAGES

1. Dry and cooler temperatures over the weekend

2. Pattern shift at the beginning of the week will bring seasonal temperatures and chances of precipitation through midweek

DISCUSSION

Current nighttime satellite is showing partly cloudy skies over the region with a few areas of patchy fog forming in central and north central OR. Overnight temperatures are expected to remain above freezing across much of the region with the exception of the cold prone mountain ridges as well as areas around Seneca where temperatures will be slightly below 30 degrees.

Hi-Res models show a weak southwest flow has settled over the region as the upper level ridge moves east and the upper level low moves down the coast. This flow regime will keep the region under dry conditions with near normal to slightly above normal temperatures. In house calculations show temperatures to be 1-5 degrees above seasonal normal. NBM shows temperatures to be in the low to mid 60s for much of the region with a few areas along the eastern mountains seeing low 70s through Wednesday.

By Monday models show the upper level low to be shifting south off the coast of Oregon and bringing a sharper southwest flow over the region. Models are in firm agreement that a closed low will form and traverse towards the coast of California and stretch as far north as Oregon. Clusters differ slightly in the track and the amplitude of the low, but are in agreement with it shifting south and undercutting the region By Tuesday and Wednesday. The variance in the amplitude will determine the amount of rainfall expected as models show the potential for wrap around moisture making its way into the region from the east. NBM raw ensembles show a 20-40% chance of precipitation for the aforementioned areas Wednesday. By Thursday, NBM raw ensembles show a 30-60% chance of precipitation becoming widespread across the region.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

VFR conditions will persist through the forecast period. Winds will be generally diurnally/terrain driven and below 10 kts. CIGs will vary from FEW250-BKN250 through the period.

Preliminary Point Temps/PoPs

PDT 64 36 62 37 / 0 0 0 0 ALW 65 42 62 41 / 0 0 0 0 PSC 66 36 64 35 / 0 0 0 0 YKM 64 39 63 38 / 0 0 0 0 HRI 65 37 63 36 / 0 0 0 0 ELN 61 35 60 33 / 0 0 0 0 RDM 63 29 59 28 / 0 0 0 0 LGD 68 39 68 36 / 0 0 0 0 GCD 72 38 70 36 / 0 0 0 0 DLS 68 43 66 41 / 0 0 0 0

PDT WATCHES/WARNINGS/ADVISORIES

WA...None. OR...None.