STORM WATCH

An Impressive Storm:

Western Washington prepares for hurricane force winds and flooding rains. See below for an excerpt from this morning’s NWS discussion. 

So what can be Stevens Pass expected from this storm?   This storm is tracking south to north with most of the energy remaining west of the Cascade Crest.  This storm is also moving fast which tends to decrease the sustained rain events. Models have some upper level ridging behind the storm late tonight which could create some breaks in the precipitation tomorrow. The atmosphere will remain unstable enough to have rain showers in the forecast into early next week.  

Rain:  Water values for the Stevens are +-75” for the next 24hrs.  Compared to the coast, the rain will be relatively light in the mountains.  

Snow:  Snow levels this morning are around 4500’ with freezing levels 5500’.  Temperatures are on the rise with warm air accompanying this storm.  Freezing levels are expected to climb to 7000’ or higher this afternoon/evening and then drop back to +-5500 tomorrow.  The upper mountain has some nice snow on it from yesterday and will likely stick around for awhile.

Wind:  The winds will shift from east to south/southwesterly later today.  Stevens Pass is usually protected from strong south-southwest winds.  However, some models are forecasting 70+ mph winds hitting the coast - so the potential for damaging winds at Stevens Pass is there.

National Weather Forecast Discussion for 10/15 3am.

A powerful storm that will impact the area later today was

presently near 43N 132W at this time. Earlier, while frontogensis

was still occurring, a ship reported sustained winds of 45 knots

(52 mph) just west of the low center. This system continued to

strengthen and is forecast to near 970 mb before moving across or

in the vicinity of Cape Flattery. This is classic set-up for a

major windstorm for western WA, especially since it contains the

remnants of Typhoon Songda. Therefore, expect fairly widespread

high winds later today through this evening, especially over the

coast and areas north of Everett. The GFS MOS guidance has

sustained winds of 37 knots (43 mph) at Hoquiam late today and 41

knots (47 mph) at Oak Harbor this evening. Winds this strong,

accompanied by 60+ mph gusts, could cause quite a bit of damage.

The storm is fast-moving; therefore, wind should rapidly diminish

after midnight tonight.

The main concern is the potential for stronger winds than

currently forecast. The bent-back occlusion is expected to move

across the coastal waters, possibly clipping the far north coast,

later today through early this. There is a real possibility that

winds could reach hurricane force over parts of the coastal

waters, with 75 mph (or higher) over the adjacent land areas. Will

need to monitor this closely over the next few hours.

The air mass will become unstable behind the front late tonight

for isolated thunderstorms over the coastal waters. Expect showery

conditions on Sunday across the entire CWA. There may be a threat

of thunderstorms over the coast and southwest interior during the

day Sunday but confidence was not high; therefore, thunderstorms

were left out of the forecast.