Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/19/24
Area Forecast Discussion
National Weather Service Amarillo TX
619 PM CDT Sun Aug 18 2024
...New AVIATION...
.SHORT TERM ...
(This evening through Monday night)
Issued at 244 PM CDT Sun Aug 18 2024
Hot temperatures will continue to be the main story line for the
short term period. After another day of widespread triple digit
temperatures today, highs tomorrow for areas across the north are
forecast to be lower due to a weak cold front.
According to the latest 18/18z H500 RAP analysis, the center of
the upper level high is sitting right over the Texas and Oklahoma
Panhandles. With the high pressure in place over the CWA,
temperatures have risen into the upper 90s and up to 107 so far
this afternoon. West to southwest downslope winds are also aiding
in increasing these temperatures today when compared to the last
couple of days. These winds are also bringing in drier air with
surface dew points well below the last few days. Even though some
cumulus are currently developing across the far west and
southeastern TX Panhandle, current expectation is that the
Panhandles will remain dry today.
The upper level high is forecast to remain over the area once
again tomorrow. However, temperatures are not forecast to be as
hot tomorrow due to a weak surface front moving into the northern
Panhandles during the morning hours. How far south the front gets
tomorrow varies in the model guidance, but at least the northeast
looks to be behind the front which will keep temperatures in the
90s for highs tomorrow. Further south, another day of dangerous
heat is expected with some locations reaching 105 degrees or
higher once again. Model guidance again does not agree with how
far south the front will move during Monday night into Tuesday
morning. In any case, no impacts are expected regardless of how
far south the front moves during the overnight hours.
Muscha
&&
.LONG TERM...
(Tuesday through next Saturday)
Issued at 244 PM CDT Sun Aug 18 2024
Not much change to the long term forecast compared to what was
seen 24 hours ago. The strong upper level ridge of high pressure
which has dominated the weather pattern the past several days is
progged to persist through Saturday with some minor variations in
location at times. This suggests above normal temperatures along
with generally dry weather will continue through Saturday. Medium
range models and various ensemble members are in reasonable
agreement with the overall pattern and were accepted. The NBM
temperatures and pops reflect the above scenario and were included
in the appropriate grids.
02
&&
.AVIATION...
(00Z TAFS)
Issued at 616 PM CDT Sun Aug 18 2024
VFR conditions are anticipated to persist through this forecast
period. Southwesterly winds that are present will turn southerly
tonight, then turn southwesterly to westerly during the day
tomorrow. Will have to watch a weak cold front tomorrow as it may
move into KGUY, changing the winds to easterly. However, do not
have confidence yet to include the easterly winds in the TAF.
Regardless, winds will be around 10 kts if not less.
&&
.PRELIMINARY POINT TEMPS/POPS...
Amarillo TX 72 102 69 100 / 0 0 0 0
Beaver OK 70 95 66 93 / 0 0 0 0
Boise City OK 66 96 64 94 / 0 0 10 10
Borger TX 73 105 70 103 / 0 0 0 0
Boys Ranch TX 70 102 69 102 / 0 0 0 0
Canyon TX 69 101 66 100 / 0 0 0 0
Clarendon TX 73 105 69 101 / 0 0 0 0
Dalhart TX 66 98 65 98 / 0 0 0 0
Guymon OK 67 94 65 93 / 0 0 10 0
Hereford TX 68 101 66 102 / 0 0 0 0
Lipscomb TX 72 101 68 96 / 0 0 0 0
Pampa TX 72 102 67 98 / 0 0 0 0
Shamrock TX 73 104 69 100 / 0 0 0 0
Wellington TX 73 107 70 103 / 0 0 0 0
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...Heat Advisory until 8 PM CDT this evening for TXZ004-005-008>015-
018>020-317.
Heat Advisory from noon to 8 PM CDT Monday for TXZ018>020-317.
OK...Heat Advisory until 8 PM CDT this evening for OKZ003.
&&
$$
SHORT TERM...05
LONG TERM....02
AVIATION...52
Area Forecast Discussion
National Weather Service Boise ID
846 PM MDT Sun Aug 18 2024
.DISCUSSION...Isolated thunderstorms in s-central Idaho, from
Camas County south to Twin Falls County should weaken and end by
midnight per latest hi-res models. Some of the storms will be
capable of producing small hail, gusty winds, and heavy
rainfall. This area remains on the western fringe of monsoon
moisture while the remainder of the area is within a dry and
stable southwest flow aloft. The pattern changes little through
Monday, although the convection may be further north and include
the West Central Mountains east of McCall in the afternoon. No
updates planned this evening.
&&
.AVIATION...VFR, except localized MVFR/IFR and mountain
obscuration in the Idaho mtns due to wildfire smoke.
Thunderstorms near/at KTWF and KJER, producing outflow winds to
30 kt, heavy rain, frequent lightning, and small hail, ending
around 19/06Z. Surface winds: variable 5-15 kt, except E-SE
10-20 kt MUO to KJER overnight. Winds aloft at 10kft MSL:
generally S-SW 15-30 kt.
KBOI...VFR. Haze in the morning. Surface winds: becoming SE
5-12 kt after 19/04Z, then light and variable after 19/10Z.
&&
.PREV DISCUSSION...
SHORT TERM...Tonight through Tuesday night...Isolated
thunderstorms are expected to develop by 3 PM MDT today along
the Idaho/Nevada border due to increased instability, moisture,
and shear ahead of an approaching embedded shortwave. The most
favorable conditions for storms are expected east of a line from
Mountain Home to Banner Summit through the evening. Surface-
Based CAPE values around 300 J/KG and 0-6 KM shear near 40 KTS
suggest organized storm development is likely across southern
Twin Falls County and the Western Magic Valley, with a 30%
chance of occurrence. Stronger storms or clusters may produce
outflow winds up to 50 MPH, blowing dust, and brief heavy rain.
Theres a 20% chance that this activity could shift into the
central Idaho Mountains later, mainly south of Banner Summit.
For Monday, the weather pattern remains largely unchanged with
an upper-level low to the west and a ridge over the Four Corners
region. Temperatures will stay in the upper 80s to low 90s in
the valley. However, monsoonal moisture is expected to reach
further north, bringing a slight 20% chance of thunderstorms
from the western Magic Valley to eastern Valley County Monday
afternoon and evening.
By Tuesday, the upper-level ridge is forecasted to shift
further east, leading to slightly lower temperatures in the
upper 80s and pushing monsoon moisture out of the forecast area.
However, increasing Pacific moisture and dynamics could provide
a slight 15% chance of thunderstorms over the higher terrain of
Baker County in southeast Oregon Tuesday afternoon.
Smoke may return to the valleys in the mornings as
early as Monday, with light diurnal winds expected. The latest
HRRR model shows less smoke than previous runs, but recent
fires, particularly the Middle Fork Complex fires in the Boise
mountains, have been very active, trapping smoke in the mountain
valleys. Theres at least a 30% chance of a smoky commute in
the Treasure Valley on Monday and Tuesday mornings.
LONG TERM...Wednesday through Sunday...As a weak longwave
trough continues to influence the Pacific Northwest on
Wednesday, a stronger, closed upper low will move south along
the coast of southwestern Canada, reaching the Pacific Northwest
by late Thursday. The weakening initial low will pass to the
north, leaving only a slight chance of showers and thunderstorms
over the higher terrain of Baker County. Otherwise, conditions
should remain dry with temperatures slightly below normal.
By Thursday, as the new upper low moves south along the coast
from Washington to Oregon, moisture is expected to spread
farther south and east into eastern Oregon, bringing a chance of
precipitation to most of Baker County, far northwest Malheur
County, and much of Harney County. The low will reach northern
California on Friday, leading to at least a slight chance of
showers and thunderstorms across most of the area.
Deterministic models are now in better agreement, showing the
low center moving through the forecast area between Saturday and
Sunday. Ensemble models largely support this, with 62% of
members predicting the low will pass through on Saturday and 29%
on Sunday. The extended forecast currently favors the majority
ensemble solution, suggesting the low will move through Saturday
into early Sunday. As a result, the chance of precipitation
increases and extends across the entire area. By Sunday, the low
should be moving northeast, leaving only the northern higher
terrain with a significant chance of showers and thunderstorms
worth mentioning in the forecast..
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...None.
OR...None.
&&
$$
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DISCUSSION...BW
AVIATION.....SH
SHORT TERM...JDS
LONG TERM....JDS
Area Forecast Discussion
National Weather Service Gray ME
1045 PM EDT Sun Aug 18 2024
.SYNOPSIS...
Widespread showers and some thunderstorms are expected Monday
into Tuesday as the trough and associated frontal system crosses
the region. Long period swell from Ernesto tracking well
offshore will bring a high surf and a high rip current risk through
Monday. High pressure builds in from the west Wednesday for
mostly dry weather through the end of the week.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
1045 PM Update...We`re experiencing a bit of a lull in showers
being in between waves at the moment. PoPs have been scaled back
over the next few hours to account for this, but chances for
showers will gradually increase again after midnight, especially
across NH. Some of these could produce heavy downpours across
southern NH after sunrise.
545 PM UPDATE...Scattered showers and low-stratus continue to
impact the region this evening. Made some updates to PoPs to
reflect where precipitation is currently. Temperatures are
running a bit colder than expected, so I opted to blend in some
of the most recent HRRR to cool off temperatures a little
through the overnight hours. No other changes were made in this
update.
PREVIOUSLY...Sfc ridging is weakening this afternoon, which
helps keep any showers that are moving in from the SW more of
the garden variety, and keeping torrential downpours out of the
area, especially considering back building cells in SW CT have
produced over 8 of rain in some spots, we will be in fine shape
for the rest of the day and overnight, with amounts likely
limited to half an inch in most. Otherwise, as the 500 MB trough
slowly moves in from the W, it will break down the sfc ridge ,
and showers will become more numerous later tonight. However we
get into a lull late this afternoon into this evening, as we
pass between waves moving in from the SW on the downstream side
of the trough. So, while there will likely be a few showers
around this evening, they will become more numerous and
widespread after midnight. Itll be on the muggy side as well
with fog developing again (at least where it didn`t last all
day), and mins in the low to mid 60s.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
Monday will feature showers in the morning, as one wave moves
through, and then maybe a bit of break midday to mid afternoon
before another round of showers moves in just ahead of the cold
front while will move into the NH mtns late in the day. If
theres going to be heavier showers, or a stronger TSRA, it will
likely be right ahead of the front late afternoon and tomorrow
evening. And there will be some dependence on some clearing or
thinning of the clouds ahead of the front as well, which will
probably be limited to S NH and the CT vly. Highs will be around
70 in the mtns to the low to mid 70s elsewhere.
As the evening showers move out, the front will begin to push
across the mtns, and it will start cooling and drying in the
mtns tomorrow evening, but the questions remains as to how much
the front mixes down SE of the mtns. Models say there is some NW
sfc flow behind the front, but its something that bears
watching. Anyway, while lows will fall into low to mid 50s in
the N, they will be closer to 60 or in the low 60s in the S.
There should be a fair amount of fog in this area too, as the
low level moisture struggles to mix out.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
A vigorous upper level trough will remain west of the region on
Tuesday. At the same time, a wave of low pressure will develop
along a frontal boundary over our coastal waters. This will
allow for more shower activity across Maine and New Hampshire
especially over northern and eastern portions of the forecast
area. Sufficient instability will be in place for the chance of
a thunderstorm as well across eastern areas. The cloud cover
and showers will keep most areas in the 60s for high
temperatures with 50s across the northern mountains.
On Wednesday, scattered showers will mostly be confined to
upslope regions of the mountains as a westerly, northwesterly
flow develops in the lower levels of the atmosphere.
Temperatures will remain below normal for this time of the year.
Similar conditions will follow on Thursday with scattered
showers mainly confined to the mountains.
On Friday, operational models and ensemble solutions suggest
height rises and some ridging will finally begin across the
Northeast. As surface high pressure settles off the Mid
Atlantic coastline, a warmer return flow out of the southwest
will develop. Afternoon highs will reach the 70s to lower 80s,
even along the coastline as sea breezes will be limited.
Relatively dry and seasonably mild conditions will follow for
the upcoming weekend.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
Short Term...All terminals, with the exception of KHIE, which
will benefit from SE downsloping, should drop to IFR or lower
during this evening, and stay there overnight, as light onshore
does little to mix anything out. KHIE may stay VFR thru much of
the night, but should eventually go down to MVFR around day
break. Its hard to see much improvement during the day on
Monday, with most terminals stuck at IFR most of the day.
Theres a small chance for a few hours of MVFR in the afternoon
away from the coast, but will see everything drop back down
again Mon evening.
Long Term...IFR conditions in any showers and possibly a
thunderstorm into Tuesday. There will also be patchy fog,
mainly during the nighttime and early morning hours. Conditions
gradually improve Wednesday into Thursday, however there still
be will isolated showers mainly confined to KHIE and the
mountains. VFR conditions will end out the week.
&&
.MARINE...
Short Term...Seas are beginning to rise as long period swell
from Ernesto moves into the waters. The forecast remains on
track with 5-6 ft near shore seas,, and 7-9 ft in the open
waters. It look like the swell peaks Monday afternoon, and
should start subsiding Monday night, but itll happen slowly.
Long Term...Long period swell from Ernesto will continue into
Tuesday. Conditions fall below SCA thresholds by midweek.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...High Surf Advisory until 8 PM EDT Monday for MEZ023>028.
NH...High Surf Advisory until 8 PM EDT Monday for NHZ014.
MARINE...Small Craft Advisory until 8 AM EDT Tuesday for ANZ150-152>154.
Small Craft Advisory until 8 PM EDT Monday for ANZ151.
&&
$$
UPDATE...Combs
NEAR TERM...Cempa
SHORT TERM...Cempa
LONG TERM...Cannon
Area Forecast Discussion
National Weather Service North Platte NE
625 PM CDT Sun Aug 18 2024
.KEY MESSAGES...
- Broad warm air advection continues across north central
Nebraska will lead to scattered rain and thunderstorms
through late afternoon, though no severe weather is expected.
- Additional morning rain and thunderstorm chances exist each morning
Monday and Tuesday for portions of western and north central
Nebraska with a low threat for severe weather.
- Temperatures continue to rise towards the latter half of the
week with a return to upper 80s to lower 90s.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 439 PM CDT Sun Aug 18 2024
Afternoon satellite imagery shows low-level stratus remaining
stubborn for areas generally along and east of Highway 61. KLNX VWP
data shows strong southeasterly flow continuing just off the
surface with 20 to 30 knot flow around 1km AGL. A narrow
corridor of focused lift is driving weak convection within the
general stratiform precipitation. This activity should wane over
the next few hours as convergence decreases.
Later today, a surface boundary draped from north to south across
the Panhandle will be a feature of interest. Daytime cumulus has
increased in coverage in close vicinity of this. This is occurring
in an area of weak convergence but underneath strong capping.
Forecast soundings show little to no erosion of this capping
inversion and lift, likely remaining weak, should preclude any
shower or thunderstorm development. Therefore, have maintained a dry
forecast for our western zones through this evening. For later
tonight, expect a modest LLJ to persist over the area. Focus will be
less favorable than Sunday morning, as well as the background
environment being less favorable. With weakening h5 flow, deep-layer
shear will be marginal and elevated instability limited to around
1500 j/kg or less. HREF probabilities are maximized in the pre-dawn
hours Monday but individual ensemble member support is limited. The
most bullish solution is FV3 guidance, however, recent runs of the
HRRR have been trending towards a similar solution. Have elected to
cover with Slight Chance (< 25%) PoPs for the time being. Have a
fairly broad coverage across the entire area though the outcome is
likely to remain fairly isolated with most locations likely staying
dry. Lows will fall into the 60s, or roughly 5 to 10 degrees above
normal.
&&
.LONG TERM /MONDAY THROUGH SUNDAY/...
Issued at 439 PM CDT Sun Aug 18 2024
Overall pattern remains stagnant through the extended period.
Amplified ridging along builds north along the lee of the Rockies
with center of high pressure across the Southern High Plains. This
will promote warming temperatures through the first half of the week
as highs climb into the 80s to low 90s west of Highway 83 by Tuesday
and upper 80s to upper 90s for all by Wednesday. A few perturbations
within the mid-level flow will round the dome of high pressure,
maintaining low-end PoPs each day through midweek. Greatest
confidence arrives Monday evening into early Tuesday morning as a
shortwave traverses the Northern Plains. NBM probabilities for
wetting rains are generally limited at 20 to 30 percent. Additional
rain and thunderstorm chances will return for Wednesday, but NBM
signals are less impressive locally with focus along the Front Range
of Colorado. Thereafter, precipitation probabilities drop off
considerably with NBM percentage values of exceeding 0.25" being 10%
or less each day Thursday through the following weekend. This
coincides with a strengthening of the upper-level ridging as h5
heights approach 600 dam across the Southern Plains. NWP guidance
varies on placement of main ridge axis, with local implications
being a more docile zonal flow locally or more southwesterly flow
ahead of the next deep trough set to approach the area towards the
end of the forecast period. Temperatures will continue to climb late
week into the following weekend with the latest forecast calling for
widespread 90s to near 100 for Saturday. Evolution of the next big
disturbance casts doubt on the extended forecast as deterministic
solutions vary considerably with placement and timing of ejection.
For now, consider days 6-10 to be fairly low confidence until model
guidance can resolve these discrepancies.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 625 PM CDT Sun Aug 18 2024
A stratus cloud deck will continue to result in localized MVFR
ceilings through the overnight for western and north central
Nebraska terminals. Potential exists for a period of IFR
ceilings toward sunrise, mainly for southern Neb (LBF). VFR
should return by mid-morning tomorrow as south/southeast winds
strengthen slightly.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...NMJ
LONG TERM...NMJ
AVIATION...Snively
Area Forecast Discussion
National Weather Service San Francisco CA
538 PM PDT Sun Aug 18 2024
...New AVIATION, MARINE...
.SYNOPSIS...
Issued at 1246 PM PDT Sun Aug 18 2024
Temperatures at or slightly below seasonal averages continue through
the next week, along with breezy onshore flow and early morning
stratus. A passing disturbance to the north will result in a few
isolated showers north of the Golden Gate Friday.
&&
.SHORT TERM...
Issued at 115 PM PDT Sun Aug 18 2024
(This evening through Monday)
Current situation: After some morning clouds/fog mostly sunny
skies prevail across the region. The exceptions are some patchy
clouds piling along the coast and a few afternoon cumulus popping
over the S Gabilan Range. Despite some afternoon sunshine
temperatures are struggling to reach seasonal average. Highs will
ultimately top out in the upper 50s to 60s along the coast and
60s to lower 80s inland, which is 5 to 15 degrees below average.
Weak onshore flow is resulting in some breezy winds along the
coast and inland gaps/passes with gusts 20-25 mph.
The bigger picture: Longwave wave pattern over the CONUS has some
Omega Block vibes too it. An upper low parked over the PacNW,
upper ridge over the Plains, and an upper low over New England.
The upper low part of the Omega Block has some perturbations
flowing through it resulting in active weather over the PacNW
(recent lightning near Seattle). So what does this mean for us in
CA? Repetitive weather in the near term. A mixed version of the
marine layer with some stratus, patchy fog, and possibly some
drizzle. Additionally, below normal temperatures will persist
despite meager warming on Monday. Highs will be in the 60s to
mid 70s coast and 80s to lower 90s inland.
&&
.LONG TERM...
Issued at 135 PM PDT Sun Aug 18 2024
(Monday night through next Saturday)
The ridge portion of the quasi-Omega block nudges westward on
Tuesday leading to a additional few degrees of warming. The
building 500 mb heights will help to compress the marine layer a
little. Warmest inland locations will soar into the upper 80s/90s
with far S interior locations making a run for 100 degrees
(40-60% chc).
The flexing upper ridge quickly retreats eastward Wednesday as an
embedded shortwave trough rounds the base of the PacNW upper low.
Temps will begin to trend cooler as the marine layer redevelops.
Had added some light drizzle back to the forecast for Wednesday
night into Thursday. Coastal fog will also be an issue again.
The second half of the week into next weekend becomes more active
as the upstream upper low final gets kicked. Decent agreement
among ensembles and cluster analysis (minor diff on timing/depth)
with an upper low dropping into CA late Thursday and Friday.
Deterministic agreement is a different story with a wide variety
of outcomes. Following the ensemble approach temperatures cool
further Thursday and moreso Friday. EFI shows below seasonal
averages through the period as well. The wrinkle in the forecast
will be precip. Latest guidance does bring some scattered showers
into the North Bay Friday, but nothing south of the Golden Gate.
While there is some instability, think best chance for actual
thunder will be north of the forecast area. Therefore, will keep
with a low chc (15-20%) for showers. Not expecting much in the
way of accumulation.
Drier weather returns next weekend with a warming trend.
&&
.AVIATION...
(00Z TAFS)
Issued at 538 PM PDT Sun Aug 18 2024
Drier and cooler surface air is arriving on northwest winds over
the coastal waters, late afternoon satellite imagery shows only a
few narrow bands of coastal low clouds otherwise it`s VFR. 24 hour
trends also show dewpoint temperatures have lowered (drying) across
the Bay Area and north Central Coast. High resolution model
forecasts including HREF are currently over-forecasting low cloud
cover, a few patches of low clouds vicinity Point Arena and areas
northward are also trying to redevelop, the HRRR shows this is
where the next area of low clouds will likely develop and move
southeastward after sunset. For inland -- it`s a high confidence
VFR forecast for the evening and along the immediate coastline --
it`s a moderate to high confidence VFR forecast for the evening.
Based on recent trends, rapid mix out of most of the low clouds and
arrival of drier air decided to delay forecast of low clouds
/LIFR-MVFR/ to later tonight and Monday morning. It`s drying aloft
tonight too thus radiative cooling will increase chances of low
cloud development overnight. Onshore winds are gusty with the
arrival of a new air mass, winds easing later in the evening.
LIFR-MVFR conditions mixing out by late Monday morning. Drier air
per lower dewpoint temps will continue to reside over the forecast
area Monday and Monday night. Redeveloping lower level thermal
ridging will bring back/reinforce the marine layer temperature
inversion tonight through Monday night. HREF shows coastal low
clouds tomorrow evening, onshore winds will be present e.g. the
NAM forecasts 4 mb SFO-SAC pressure gradient.
Vicinity of SFO...Moderate to high confidence VFR for the evening,
west wind gusting to 30 to 32 knots, possibly a few higher gusts,
will closely monitor. Initial low cloud redevelopment will likely
move across San Francisco/Golden Gate late in the evening and
overnight, for SFO forecasting tempo IFR ceiling 10z-12z then IFR
prevailing until 1730z Monday. VFR thereafter with a west wind
increasing to near 30 knots Monday afternoon and evening.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...Recent satellite imagery showing low clouds
steadily mixing out on northwest winds. Moderate to high confidence
VFR forecast for the evening, then increasing probability of IFR
ceilings developing near midnight into Monday morning. IFR ceiling
lifting to VFR by late Monday morning. Onshore winds 5 to 15 knots
with a few gusts to 20 knots with newly arriving air mass from the
northwest.
&&
.MARINE...
(Tonight through next Friday)
Issued at 450 PM PDT Sun Aug 18 2024
Surface high pressure over the offshore waters will result in
northwest winds this week. An upper level low pressure system from
Alaska will dig southward reaching the Pacific Northwest and far
northern California late this week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.
&&
$$
SHORT TERM...MM
LONG TERM....MM
AVIATION...Canepa
MARINE...Canepa/Sarment
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Area Forecast Discussion
National Weather Service Pocatello ID
152 PM MDT Sun Aug 18 2024
.SHORT TERM...Today and Monday. Looking at current satellite
imagery, there continues to be a deep upper level low centered
just off the coast of Oregon and Washington. Plus, there is a
ample lingering moisture over our area as well as additional
moisture moving northeast into our area today.
Later this afternoon, starting around 3 to 4 pm, look for
isolated to scattered showers and thunderstorms across the area
with our eastern areas along the Wyoming border having the best
chance for thunderstorms. These eastern areas are also under a
marginal risk for severe thunderstorms from the Storm Prediction
Center. Expect gusty winds around 40 mph to 50 mph with wind gusts
up to 60 mph. Also, expect small to moderate hail along with
moderate to heavy rainfall under thunderstorms. Our eastern areas
are also under an excessive rainfall outlook mainly along the
Wyoming border. Again, this is the area where thunderstorms are
the most likely to occur as well as be the strongest. Precipitable
water content of around 1 inch is expected in the Eastern Magic
valley, Snake plain, and our Eastern areas along the Wyoming
border.
Tonight into Monday, models show our area in the same pattern,
with an upper level low off the Oregon coast and moisture still
moving up from Utah into our area combined with lingering
moisture. Look for isolated to scattered mostly afternoon showers
and thunderstorms over most of our forecast area on Monday as
well. Look for mainly scattered thunderstorms along the Wyoming
border in our our area Monday afternoon. Strong outflow winds are
expected again with these thunderstorms. Our eastern areas along
the Wyoming border are also under a marginal risk again for
severe thunderstorms mainly due to strong outflow wind gusts.
Plus, these same eastern areas bordering the Wyoming border are
also under an Excessive Rainfall Outlook for Monday afternoon.
Small to moderate hail and brief heavy rain are also expected.
Expect temperatures today and Monday above normal for this time
of year due, in part, to southerly flow. Look for mid to upper
80s with some lower 90s across our lower elevations.
Wyatt
.LONG TERM...Tuesday through next Sunday.
Models show a drying trend Tuesday through early Thursday. Models
then continue to show moisture moving back in the area late
Thursday into next weekend. Model clusters are in good agreement
in bringing an upper level low through the area on Saturday.
Temperatures will start the week near normal, if not slightly
above normal, and will stay that way through Thursday. Friday
temperatures, with precipitation chances returning, will start
trending downward and look to be 4 to 8 degrees below normal on
Saturday and Sunday, days where good precipitation chances are
expected.
Wyatt
&&
.AVIATION...
The primary impact to terminals and aircraft today will be strong
outflow winds from thunderstorms, which will range 45 to 55 kts. The
strongest storms are expected to be capable of producing pea to
nickel size hail and locally moderate to heavy rainfall. Outside of
storms, expect light to breezy winds with gusts to around 20 kts.
Showers will linger through late night before clouds clearing from
west to east overnight and during the morning hours.
Cropp
&&
.FIRE WEATHER...
Red Flag Warnings are in effect from 3 PM to 10 PM today for Fire
Weather Zones 410, 413, 422, 425, and 427 due to scattered
thunderstorm coverage. Thunderstorms will be capable of producing 50
to 60 mph outflow winds, locally moderate to heavy rainfall, and pea
to nickel size hail. Outside of thunderstorms, wind gusts will reach
up to around 25 mph. A drier air mass will move into central and
eastern Idaho tomorrow and Tuesday. More widespread minimum
humidities below 15% and wind gusts over 25 mph on Tuesday may
necessitate another Red Flag Warning for portions of central Idaho.
Cropp
&&
.AIR QUALITY...Southerly flow has cleared out our area, including
Custer County, bringing good air quality today. The HRRR model
continues to show good air quality across the area today with
southerly flow aloft, as long as there are no new fire starts.
This southerly flow aloft pattern should stay in place through
Monday, which will keep the smoke away from the area (again as
long as there are no new fire starts).
Wyatt
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 10 PM MDT this evening for IDZ410-413-422-
425-427.
&&
$$