702
FXUS66 KOTX 191248
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
439 AM PDT Wed Jun 19 2024

.SYNOPSIS...
Showers and isolated thunderstorms will again develop today across
across the northern mountains. A warming trend is expected
through the week, with high temperatures rebounding into the mid
80s to mid 90s on Saturday. A dry cold front on Sunday will create
elevated fire weather concerns with widespread breezy winds
across the region.

&&

.DISCUSSION...
Today through Thursday Night: The weather pattern of a long wave
trough over the western US and a strong ridge over the central and
eastern US persists the next couple days. Yet there continues to
be some subtle changes in the details that will bring about a
warming trend with less convection as compared to the past couple
days. For today the flow aloft will be lighter over the region
resulting in convection focused more over the mountains. There
will also be drier air (lowering precipitatable water) moving into
southern WA and the lower ID Panhandle. The net result will be
convection limited to mainly the northern mountains. Uncapped
surface based CAPE of 500-1000 J/KG will lead to another round of
scattered showers and isolated thunderstorms over these areas this
afternoon into the early evening. The NAM and ECMWF also show
some convective qpf this afternoon over the Blue Mountains and
Camas Prairie so added a mention to the forecast for this area.
One last thing to mention today, and that is early morning fog.
Areas of clearing overnight after yesterday`s shows has allowed
patchy coverage to form in the valleys of NE Washington and the
Idaho Panhandle. The early AM sunrise and shallow coverage will
result in fog lifting or burning off by 8 AM.

On Thursday the drier air pushes north into NE Washington and N
Idaho. This should result in even less convection over the region,
except for a 20 percent chance over the Cascades as a weak wave
passing combined with afternoon heating may be enough to generate
isolated showers or thunderstorms. Lastly, prior to the Thursday
afternoon convection potential the NAM is showing a weak wave
passing through the Columbia Basin and Palouse Thursday morning.
There is some weak elevated instability that could result in a few
high based showers. Most likely if anything develops precip would
evaporate before reaching the ground so kept the forecast dry.

The trending of less convection and more intense mid-June sun the
next few days will support the beginning of a warming trend.  JW

Friday through Tuesday: A ridge of high pressure will amplify over
the region heading into the weekend, warming high temperatures into
the upper 80s and even mid 90s for some locations by Saturday. It`s
looking like Friday and Saturday will be beautiful for outdoor
activities. Just be sure to stay hydrated and take breaks in the
shade as needed!

By Sunday the ridge will begin to push eastward, and a trough will
quickly take its place over the Inland Northwest. While the trough
is not looking to carry any moisture with it, it will create a
pressure gradient resulting in winds picking up regionwide Sunday
afternoon. Gusts ranging from 20 to 30 mph are expected. There is
potential for gusts up to 40 mph through the Cascade gaps and over
the Waterville Plateau. Temperatures will be several degrees cooler
than Saturday`s, but with dry, breezy conditions in place, rapid
spread of fires will still be a concern. SPC is already highlighting
Central and Eastern WA for potential fire concerns on Sunday.

Temperatures will cool a few more degrees Monday due to the
continued influence of the trough before we transition into a more
zonal flow pattern and temperatures rebound toward mid next week.
/Fewkes

&&

.AVIATION...
1245z Update - Fog expanded in the past hour around the Spokane area
and advected into KGEG.  TAF has been amended to include fog through
1430z before gradually lifting 1430z-16z then dissipating.

Previous TAF discussion:

12z TAFS: Ground fog has developed over many valleys of NE
Washington and North Idaho including Bonners Ferry, Sandpoint, and
Coeur d`Alene, with a few patches around Spokane Felts Field as
well. With the sunrise at 12z, the time for fog to expand further
is closing, so went near persistence compared to 11z obs for the
first 3 hours, which included IFR conditions at KCOE. Did include
a tempo group at KSFF as well (although confidence in precise
restrictions is low). For this afternoon another round of showers
and thunderstorms will develop over the northern mountains. There
is a 20% chance of thunderstorms for the northern airports from
Winthrop through Omak, eastward through Republic, Colville,
Sandpoint, and Bonners Ferry.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: There is high
confidence of IFR conditions at KCOE 15z, with improvement by 17z
with the high mid-June sun angle. Confidence is lowest at KSFF and
KGEG given fog near these airports, but with time running out for
fog expansion the most likely scenario is for prevailing
conditions to remain VFR, with a moderate chance of a temporary
restriction at KSFF. High confidence in continued VFR conditions for
the other TAF sites (KMWH/KEAT/KPUW/KLWS). JW

-----------------------

Confidence descriptors:
Low - Less than a 30 percent chance
Moderate - 30 to 70 percent chance
High - Greater than a 70 percent chance

For additional probabilistic information for NWS Spokane airports,
please refer to the Aviation Dashboard on our webpage:
https:/www.weather.gov/otx/avndashboard

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  47  81  53  85  55 /  10   0   0   0   0   0
Coeur d`Alene  72  46  80  51  83  51 /  10   0   0   0  10   0
Pullman        74  47  81  51  82  52 /   0   0   0   0   0   0
Lewiston       84  53  90  59  91  58 /   0   0   0   0   0   0
Colville       72  40  79  44  84  48 /  30  10   0   0  10   0
Sandpoint      70  45  78  49  81  49 /  20  10   0  10  20   0
Kellogg        70  49  79  55  79  56 /  10   0   0  10  20   0
Moses Lake     82  52  87  55  92  58 /   0   0   0   0   0   0
Wenatchee      80  56  85  60  90  64 /   0   0   0   0   0   0
Omak           78  51  84  54  90  57 /  20  10   0   0   0   0

&&

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

$$