Marine Weather and Tide Forecast for Klickitat, WA

DISCUSSION
Today is the warmest day of the 7 day forecast period, at least as far as this deterministic forecast goes. Widespread 70s and even some low 80 degree highs are expected this afternoon (low 80s in central Oregon, John Day, Lower Columbia and Kittitas Valley). The warmed up airmass will couple with plenty of cloud cover overnight, remaining mild in the upper 40s to around 50 degrees in the non mountains zones by early Tuesday morning.

Widespread precipitation will develop across the area Tuesday and Wednesday with the bulk of the precipitation falling on Wednesday, especially in the first half of the day. Interestingly the IVT/IVW portal shows a lingering swath of 200 to 300 kg/ms through the eastern Columbia Gorge/foothill of nrn Blues by 60 hours. Clusters indicate the GFS producing the highest overall QPF amounts which can exceed 3 inches in this region of the SE WA and NE OR which may have impacts on area rivers see (hydro sections). Prior to more widespread and lower CAPE environment rains will be a period of convective potential for Tuesday afternoon and lingering through late Tuesday evening, supported by NBM thunderstorm chances in the 15 to 30% range across the eastern mountains (highest coverage potential across the Wallowa county Tuesday Evening. After the broader upper trough exits to the east on Wednesday stronger westerly boundary layer momentum is poised to cause about 50-70% chances for wind gusts to 45 mph or more across the Simcoe Highlands and Oregon Columbia Basin Wednesday afternoon. Following the midweek system, ensembles favor a ridge developing over the PAC NW resulting in a dry and warming period into week 2. Russell/71

AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/
VFR conditions to prevail through the period. An upper low moving into the region will bring rain shower chances to northern sites in the afternoon tomorrow, while sites RDM/BDN will see increasing chances mid to late morning tomorrow. There is a <20% chance of thunder at most sites, and given the showery nature have not included mention at any site at this time. Winds will mostly be light tonight, then increasing to 12-20kts with gusts 20-30kts at sites DLS/PDT/YKM/ALW/PSC tomorrow afternoon, with winds starting late morning at site DLS. Winds will be mostly 12kts or less at sites RDM/BDN. Lawhorn/82

HYDROLOGY
Area has undergone a warm spike in recent days which continues into Tuesday, leading to melting of the limited amount of snow that is on the northern Blues/Cascades crest. This will lead to elevated river levels prior to the onset of the rains which are NBM mean in excess of 2 inches across the areas of the northern Blues, by Thursday afternoon (Cascade Crest of WA will be limited to around a half inch of total QPF). Based on HEFS at this time, these rivers remain broadly forecast below the minor flood stages, which suggests a less than 10% chance for minor flooding with current snow melts and range of QPF as input.
Several rivers including the Naches and Grande Ronde/Walla Walla have river points forecast to reach close to or exceed action stage by Wednesday night, and fall by the weekend. Russell/71

Preliminary Point Temps/PoPs
PDT 47 72 44 53 / 10 40 90 90 ALW 53 73 45 52 / 0 20 90 100 PSC 49 78 49 63 / 0 10 70 80 YKM 50 76 50 65 / 10 20 50 40 HRI 48 74 46 58 / 0 20 80 80 ELN 48 70 45 56 / 10 30 50 40 RDM 44 61 36 53 / 20 50 50 40 LGD 44 74 41 47 / 0 40 100 100 GCD 44 69 39 47 / 10 70 100 90 DLS 53 66 49 59 / 20 30 40 60

PDT WATCHES/WARNINGS/ADVISORIES
WA...None.
OR...None.