The National Weather Service now has a flash flood warning due to potential thunderstorms over north-central Washington, from the North Cascades northeastward.
Convective storms, some with thunder and lightning, did occur yesterday (Sunday) over the Cascades and were even visible from Seattle:
The convection/thunderstorms yesterday produced precipitation over northeast Washington (see totals below), with only modest lightning.
Today there is potential for more unstable air, convective showers, and some lightning and thunder over and east of the Cascades.
The visible satellite at 9 AM this morning shows considerable cloudiness over the region, with some convective cells evident over south-central WA (whiter areas).
The current (10:42 AM) weather radar is picking up some showers with this convection/instability:
Today's model runs are emphatic that convective showers will develop this afternoon over the Cascades, the Okanogan, and northeast WA.
Here is the simulated radar impact at 3 PM from the UW WRF model, with the orange colors showing the heaviest rain from the convection.
The forecast of the NOAA HRRR model at the same time is similar.
The total precipitation through 5 AM Tuesday (shown below) is moderate, with highest amounts reaching 1.5 inches. Not enough for flooding.
The occurrence of this precipitation is associated with an upper-level low over eastern WA (see map today at 2 PM for around 18,000 ft).
My only worry about this event is that the associated lightning could start some wildfires. One reason we have had such few fires this summer is the lack of lightning-induced fires.
This is not an accident: the same large-scale conditions that gave us a dry summer have also reduced lightning.
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Already several rounds of thunder east of the Methow...
ReplyDeleteCool photo of the convective storms from Seattle. I did not know we could see that.
ReplyDeletePlease stay safe, people of Central Washington. There may not be flooding, but that doesn't mean this isn't a dangerous situation.
ReplyDeleteNot a drop in city of Olanogan. Omak 4miles north got a tad bit. Big bummer..
ReplyDeleteWe heard thunder and got a nice wetting near Cle Elum. About 0.2" which is a lot for this time of year. It was very welcome.
ReplyDeleteI was in the Cascades today, mostly between Rockport and Washington Pass. I almost forgot to bring raingear, and that would have been a bummer. I was talking to someone outside of Marblemount whise backyard rain gauge picked uo 1.5" in about 45 minutes.
ReplyDeleteI didn't see any flash flooding, but some of the runoff in burned areas was definitely getting frisky at times.
A quick look at early summer (06/21 - 07/21) precipitation for KBLI:
ReplyDeleteDuring the POR (1949 - present) for this site, early summer precipitation has decreased by just over 50% from ~1.7” to ~0.8”. From 1999 to present, early summer precipitation has decreased by 48% from ~1” to just over 0.5”.
Early summer precipitation this year totaled 1.08” and is the most we’ve received for the period in question since 2019. So, despite the ongoing drought which is affecting most of the state, Western Whatcom County has largely been spared…at least so far.
The bigger story, however, is the marked decrease in early summer precipitation which has occurred throughout the POR and, rather more disconcertingly, that the rate of decrease in early summer precipitation has remained constant during that timeframe whether one looks at the entire record or just that of the 21st century to-date.
Western Whatcom County was, in the not too distant past, one of the only areas of inland Western Washington to sport a maritime/oceanic-type climate but no longer. The ratio of wet season precipitation to dry season precipitation is now large enough such that this area has transitioned into the more typical warm-summer Mediterranean-type climate common to areas further south along the Puget Sound (i.e. Everett, Seattle, Tacoma, etc.)