Flash Flood Warning 10, NWS Spokane, WA

868 
WGUS76 KOTX 282331
FFSOTX

Flash Flood Statement
National Weather Service Spokane WA
431 PM PDT Sun May 28 2023

WAC019-282341-
/O.CAN.KOTX.FF.W.0010.000000T0000Z-230529T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Ferry WA-
431 PM PDT Sun May 28 2023

...FLASH FLOOD WARNING FOR THE SUMMIT TRAIL BURN SCAR IS CANCELLED 
FOR CENTRAL FERRY COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 4847 11832 4832 11826 4834 11852 4848 11855

$$

SB

Area Forecast Discussion
National Weather Service Spokane WA
1020 AM PDT Sun May 28 2023

.SYNOPSIS...
There will be more scattered showers and thunderstorms over the
Idaho Panhandle and the mountainous terrain of northeast
Washington Today. Memorial Day will be mainly dry with afternoon
temperatures in the upper 70s to mid 80s. The arrival of a frontal
system Wednesday into Thursday will cool afternoon temperatures
into the 70s and bring the chance of showers to the Idaho
Panhandle.

&&

.DISCUSSION...

Sunday and Monday: The environment is pretty soupy across the Inland
Northwest. The 00z KOTX sounding had over 0.90" of precipitable
water which stands over 90th percentile for the date (daily max is
1.05"). Temperatures early this morning in the mid to upper 50s/low
60s are quite mild for overnight in late May. The messy upper level
pattern will begin to clear out by the end of today (Sunday). The
ejecting upper Low feature continues east into SE Idaho/SW Montana
and a westerly flow filters in across Washington. The last piece
of upper level energy/lift will move across the Cascades allowing
showers/convection to develop east of the Cascade Crest this
afternoon. CAPE values 500-1000 J/kg and precipitable water values
between 0.75 and 1.00 inches will provide thunderstorm and
showers the ingredients needed to build afternoon/evening storms.
Precipitation amounts and thunder chances look lower today than
we've seen the past several days. However, the threat for showers
and isolated thunderstorms will be focused across the northern
Idaho Panhandle and northeast WA Mountains.

Given how much rainfall we saw yesterday and the higher humidity,
some low stratus clouds are very possible (40-50% probability) for a
few hours this morning. Forecast soundings again have some tall,
skinny instability with very weak flow and a very moist profile.
We'll keep a close eye on this especially since this is a Holiday
Weekend and there are likely a higher number of folks out in the
terrain and outdoors.

Monday the flow aloft continues to shift out of the west and we
begin to see a drying trend. The boundary layer dries out quite a
bit and the southwest flow will bring in warmer temperatures. If
you're looking for which day this weekend has better (drier)
weather to take part in outdoor activities, Monday might be better
suited for you. Given our warmer than normal temperatures, please
continue to be cautious and aware of cold water safety by wearing
a life jacket around water. /Dewey

Tuesday through Saturday: Models continue to be in solid
agreement that the Pacific Northwest will remain in an overall
progressive pattern through the week. Tuesday will remain dry as
the flow aloft begins to transition from zonal to the southwest as
as upper level trough and cold front associated with a low in the
Gulf of Alaska begins to move into the region. Temperatures on
Tuesday will be in the upper 70s and low 80s (about 5 to 10
degrees above average). A weak front will move through the region
Tuesday into Wednesday with temperatures cooling by about 5
degrees on Wednesday.

Deterministic models are hinting at a more robust shortwave to
move off the Pacific and make landfall somewhere along the
northwestern coast on Thursday, but ensembles reveal multiple
potential solutions. A northerly landfall into Washington
(supported by 36% of ensembles) would result in even cooler
temperatures into Thursday and precipitation. Another 36% of
ensembles show a weaker version of the trough making a slightly
more southerly landfall, which would result in cooler
temperatures, but less precipitation. The feature does not look to
exist in the last 28% of ensembles, which would keep temperatures
on Thursday warmer. Neither scenario would be all that impactful,
but it does result in a large spread for possible maximum
temperatures for Thursday through Saturday.

Models are in good agreement that ridging will continue to build
over the central US into the weekend as the low in the Gulf of
Alaska deepens. The Inland Northwest looks to be sandwiched between
these two features, with deep southerly flow aloft. This is too far
out in the forecast to make any skillful predictions, but
this may result in another interesting period of weather for our
region. The Climate Prediction Center is highlighting this period
with high confidence for temperatures above average along with
moderate confidence of above average precipitation. Not a
combination we see too often in this region. /vmt

&&

.AVIATION...
18Z TAFS: The most concentrated shower activity has become
focused over far eastern Washington and the southern Idaho
Panhandle in the vicinity of a weak upper low (VCSH for KCOE-
KLWS). The majority of our airports should remain VFR.

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        79  53  80  53  80  52 /  20  10   0   0   0  10
Coeur d'Alene  75  53  79  51  79  51 /  30  10   0   0   0  10
Pullman        74  51  78  51  77  49 /  30  10   0   0  10  10
Lewiston       81  57  87  57  85  57 /  30  10   0   0  10  20
Colville       79  51  81  50  80  48 /  20  10   0   0   0   0
Sandpoint      73  53  78  51  78  51 /  30  30   0   0   0  10
Kellogg        70  54  77  54  77  52 /  50  20   0   0   0  10
Moses Lake     85  52  86  51  82  49 /   0   0   0   0   0   0
Wenatchee      84  54  84  54  80  52 /   0   0   0   0   0   0
Omak           85  55  86  53  82  52 /   0   0   0   0   0   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SPOKANE WA
852 AM PDT SUN MAY 28 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0442 PM     HEAVY RAIN       4 N WINTHROP            48.54N 120.19W
05/27/2023  M0.72 INCH       OKANOGAN           WA   PUBLIC

            SOCIAL MEDIA REPORTED DEBRIS ON RAVEN AND
            MCLEAN ROAD. RAIN TOTAL FROM W. CHEWUCH
            ROAD.

&&