Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/15/22

Area Forecast Discussion

National Weather Service Cheyenne WY

 951 PM MDT Wed Sep 14 2022

.SHORT TERM...(This evening through Thursday night)
Issued at 255 PM MDT Wed Sep 14 2022

Latest surface analysis shows a surface low over western SD ahead
of the upper level shortwave with a secondary surface low to the
south near the CO/WY/NE border. GOES WV imagery shows ample
moisture over the central Rockies through the northern Great
Plains that previous shifts have noted is associated with the
remnants of Kay. This moisture will be the main weather story for
the short-term period as multiple shortwaves passing in the flow
will help bring chances for scattered to widespread showers and
thunderstorms late this afternoon and Thursday.

So far this afternoon, weak convection has been tied to the
higher terrain between Cheyenne and Laramie with additional storms
in south-central WY approaching western Carbon Co. Hi-res guidance
shows fairly widespread coverage with additional storms moving
northeast out of northern CO. Weak 500mb flow will help keep
shear values below severe thresholds, while latest RAP forecast
only places 600 J/kg of MLCAPE over the Laramie Range. With the
moist column, these are fairly long, skinny CAPE profiles. East
of the Laramie Range, boundary layer moisture is much lower which
could lead to gusty, erratic winds from these storms. With the
upper level support, these storms will continue into the Nebraska
Panhandle early this evening before mostly dissipating by
midnight.

A few lingering showers will be possible headed into Thursday
morning. However, coverage will increase once again in the
afternoon with another shortwave passage. Greatest coverage of
storms looks to be along the I-80 corridor from Laramie to Kimball
in the afternoon, but the latest HRRR. Kept the cooling trend that
the NBM has had the last few days for Thursday as mostly cloudy
skies are expected and 700mb temps drop near 5C before slowly
warming back up headed into the weekend. Expecting afternoon highs
in the 60s across SE WY Thursday while much of the Nebraska
Panhandle will reach the 70s.

.LONG TERM...(Friday through Wednesday)
Issued at 255 PM MDT Wed Sep 14 2022

Long Range models in good agreement this weekend through early
next week, with some disagreement on next week`s cool down around
Wednesday and Wednesday night. For this Friday, all models show a
third upper level disturbance embedded in southwest flow aloft
moving across southeast Wyoming and western Nebraska. This feature
will help initiate scattered showers and thunderstorms across the
area, especially the eastern High Plains along/east of I-25
Friday afternoon. A few thunderstorms may become organized with
gusty winds and locally heavy rainfall possible. Not terribly
impressed with the available moisture nor low level instability,
but there should be enough forcing that a few stronger storms
can`t be ruled out. Otherwise, it will remain seasonable with
highs around 70 west of I-25, and 75 to 85 degrees east of I-25
into western Nebraska.

All models show the upper level ridge axis rebuilding over the
Front Range and adjacent Great Plains states this weekend. Still a
good chance for showers and thunderstorms Saturday afternoon, but
coverage should be lower compared to Friday with most of the
activity mainly up north. Another drying trend is expected Sunday
and Monday with highs climbing back into the upper 70s to upper
80s for southeast Wyoming and into the low to mid 90s for western
Nebraska.

As we head into Tuesday and Wednesday, models are hinting at a
well defined upper level trough pushing across the Great Basin
region. The ECMWF shows a upper level closed low into Wednesday
with much slower progression compared to the GFS and Canadian, but
a higher chance at some decent precipitation across the region
since we`ll be on the southeast flank of the low as it ejects
northeast. The GFS and Canadian are colder and more breezy with
700mb temperatures dropping to -2c to -6c by Thursday. Trended
temperatures cooler on Wednesday with good ensemble support, but
only increased POP a small amount due to timing concerns.

&&

.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 951 PM MDT Wed Sep 14 2022

A few lingering rain showers overnight for some western Nebraska
terminals and KRWL. Showers may contain gusty winds and light to
moderate rain, which could lead to brief visibility reductions. An
incoming shortwave will lead to lowering CIGs at KRWL and KLAR
during the morning hours on Thursday, leading to MVFR conditions.
Scattered showers and thunderstorms are expected during the
afternoon hours.

&&

.FIRE WEATHER...
Issued at 255 PM MDT Wed Sep 14 2022

Minimal fire weather concerns the next few days with scattered
showers and thunderstorms possible through Saturday. In addition
to the chance for precipitation, cooler weather near normal for
mid-September will help keep afternoon RHs above critical
thresholds. Fire weather concerns increase late this weekend into
early next week as a quick warm up will lead to drier conditions
across the area. Winds also look to reach critical thresholds,
especially west of the Laramie Range over much of Carbon and
Albany counties.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&

$$

SHORT TERM...MB
LONG TERM...TJT
AVIATION...SF
FIRE WEATHER...MB



AREA FORECAST DISCUSSION

National Weather Service Sioux Falls SD

 1031 PM CDT Wed Sep 14 2022

.SHORT TERM...(This Evening through Thursday)
Issued at 245 PM CDT Wed Sep 14 2022

A hot afternoon has developed with temperatures in to near 90
degrees for areas along and west of the I-29 corridor. Dew points
have remained high enough (upper 50s to lower 60s) to avoid critical
fire danger levels, but burning should still be avoided if possible
due to gusty winds at 25 to 35 mph.

Satellite images early this afternoon show wildfire smoke streaming
in aloft with a mid level wave moving through the NE Panhandle into
south central SD. This wave, combined with diurnal cooling after
sunset, is expected to induce a weakly unstable layer near/above
700mb later this evening. The 18z HRRR and 12z NAMNest guidance
generally agree on scattered high based showers and isolated
thunderstorms developing west of a Brookings to Tyndall line late
this evening and overnight. Given inverted-V soundings present, very
little rain (less than a tenth inch at any one site) is expected to
reach the surface, but this activity could bring gusty erratic
winds, occasionally mixing gusts up to 50 mph down to the sfc.
Further east, expect mostly dry conditions with increased cloud
cover and gusty winds generally in the 20s and occasionally 30s.

Overnight warm air advection in response to the low level jet will
keep nighttime low temperatures very warm, in the 60s to near 70
degrees. In fact, Mitchell and/or Huron SD will be within a few
degrees of breaking a record warm low temperature.

Expect a break in rain chances for the very early morning hours, but
rain chances increase again after sunrise as another weak
disturbance moves in via southwest flow aloft. Expect spotty showers
and occasional thunderstorms starting in south central and southeast
SD and increasing in coverage some through the day as activity
spreads east, but only a few sites have a decent shot of seeing over
a tenth inch of rain. The highest rainfall amounts are most likely
along the SD/NE border where instability is a bit higher. Severe
weather threat is very low with weak instability and unidirectional
winds with modest mid to upper level flow. Overall expect a gusty
south wind, cloudy conditions and a slightly milder day with highs
mostly in the lower to mid 80s.

.LONG TERM...(Thursday Night through Wednesday)
Issued at 245 PM CDT Wed Sep 14 2022

Periods of off and on rain chances continue Thursday night through
Saturday as upper ridging slides east and southwesterly flow aloft
brings a parade of weak disturbances through the Central Plains.
Euro/GFS ensemble and deterministic guidance suggest a swath of
showers and perhaps a few thunderstorms developing Thursday
afternoon and night across eastern SD and central to eastern NE as a
shortwave overrides an approaching cold front. 12z NAM guidance is
the drier outlier for Thursday evening, with a stronger afternoon
preceding shortwave and slower evening wave. Still have lower than
average confidence in timing and amounts, but a majority of guidance
continues to support a high (60-90%) chance of 0.10" or greater for
Thursday night, especially south of the I-90 corridor in SD/NE.

By mid morning Friday, rain chances decrease behind the wave so
should see a drier day than not. The approaching front stalls in the
region Friday with cloudy skies and cooler air resulting in highs in
the 70s to lower 80s, warmest south of the I-90 corridor. 12z
guidance suggests the next shortwave initiates convection in the
western Dakotas or Nebraska Friday evening, tracking into the region
sometime Friday evening through early Saturday morning. Although
there is lower confidence in the timing/track, an incoming mid level
jet max also supports potential for severe wx so will need to
monitor despite weaker instability being present.

If the stalled front lingers in the region Saturday, instability
will likely have amounted to enough (MUCAPE > 1500 J/kg ahead of the
front) to bring additional threat for severe wx Saturday, but this
threat is quite conditional - both on timing of any overnight
convection and any additional disturbances aloft.

There is good agreement in a pattern shift toward drier and warm
conditions from Sunday into Monday as a strong closed low comes
onshore from the Pacific and ridging over the South disrupts
moisture supply to the Central U.S. This drier, warmer pattern may
continue through mid week, but there is poor model agreement in how
longwave troughs in the West and Canadian Rockies phase by Wednesday
and beyond.

&&

.AVIATION...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 1031 PM CDT Wed Sep 14 2022

VFR conditions are expected for the TAF period. Light showers are
currently located along and west of the James River and will
continue to move north/northeast into the overnight hours. Have
left VCSH in KHON`s TAF due to the lingering light showers. The
low level jet is currently strengthening, creating LLWS at all TAF
sites. The LLWS will continue through the entire night before the
low level jet weakens during the early morning hours tomorrow.
Breezy southerly winds will continue through the night as well.

No break from the breezy southerly winds as they continue through
the day tomorrow. Another chance for showers and storms develops
late morning tomorrow and continues through the day. Have included
VCSH in all TAF sites as confidence in showers around KSUX has
increased. However, confidence remains low enough at this time to
preclude mentioning SHRA/TSRA in a TAF but trends will be monitored.
Gusts drop off during the evening hours as the boundary layer
stabilizes.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.
&&

$$

SHORT TERM...BP
LONG TERM...BP
AVIATION...Meyers



Area Forecast Discussion

National Weather Service Lincoln IL

 745 PM CDT Wed Sep 14 2022

.SYNOPSIS...
Issued at 327 PM CDT Wed Sep 14 2022

Quiet weather will persist into this weekend as heat builds into
the upper 80s. The next best chance for rain arrives Sunday night
into Monday as a weak disturbance pushes through the region.
Otherwise, the stretch of dry and progressively hotter
temperatures will continue into next week.

&&

.UPDATE...
Issued at 744 PM CDT Wed Sep 14 2022

Main concern overnight is fog potential spreading south from
northern Illinois and Indiana. Latest hi-res guidance continues to
hint at this possibility as far south as the I-74 corridor and
across portions of east central Illinois, but most of central
Illinois will remain fog free. Outside of this potential, expect
quiet weather conditions overnight to continue on the western
periphery of a ridge axis. Temps will fall into the mid to upper
50s.

&&

.SHORT TERM...(This evening through Thursday)
ISSUED AT 327 PM CDT Wed Sep 14 2022

Upper level ridging centered over Arkansas early this afternoon will
be edging eastward, with the ridge axis over Illinois by Thursday
morning. Large area of smoke remains in place over the central U.S.,
and latest HRRR smoke output continues with the thicker smoke layer
passing further north across the Great Lakes through tonight. Kept
with the higher sky cover amounts introduced earlier based solely on
the smoke, as not much in the way of cloud cover is expected until
the ridge axis shifts east.

Included a mention of patchy fog again late tonight along the
eastern and northern fringes of the forecast area. However, HREF
output favors the northern quarter of the state with low clouds and
fog, aided by a bit more of a moisture feed off Lake Michigan in the
wake of a lake-enhanced front.

With more of a southerly flow picking up on Thursday, humidity
levels will be a bit higher than recent days, with temperatures up a
few degrees from today.

.LONG TERM...(Friday through Wednesday)
ISSUED AT 327 PM CDT Wed Sep 14 2022

The upper-level ridge will continue to break down and shift eastward
through Friday as shortwave energy ejects across the Plains ahead of
a deep Pacific trough moving onshore.  Most of this shortwave energy
ahead of the main wave will be deflected north and west of our area
as central Illinois remains on the periphery of the upper ridge. The
net effect will be continued dry conditions through at least
Saturday.

Surface wind gusts will begin to increase Friday into Saturday as
the geopotential height gradients tighten in between high pressure
anchored over the SE U.S. and developing low pressure lifting across
portions of the Central Plains and Upper-Mississippi Valley.
Occasional gusts to 25 kts are likely Friday, with more frequent
25 kt gusts expected Saturday.

Temperatures will continue to surge warmer Friday and Saturday as
18degC 850-mb air advects into the region from the Southern Plains.
With sufficient mixing, this should correlate to afternoon
temperatures between 85-90degF with overnight lows cooling into the
mid 60s.

Predictability concerns begin to creep in by Sunday night after what
is likely another dry and unseasonably warm day.  In the upper
levels, the pattern will become more amplified as the Polar Jet
Stream buckles over the West Coast and heights rapidly increase
across much of the central U.S.  Most of the 12z suite of global
guidance continues to exhibit shortwave energy rippling through
veering mid-level flow.  Though most of this forcing is displaced
north of our area, it will be enough to drive a surface trough
through our northern half late Sunday night into Monday morning.
While BUFKIT soundings reveal considerable dry air in the lowest few
km, scattered high-based convection cannot be completely ruled out.

By Monday afternoon, global and ensemble guidance show central
Illinois positioned beneath another anomalous upper ridge. This will
shut off the precip chances and bring the onset of even hotter
temperatures.  Latest NBM guidance suggests low 90s Monday and
Tuesday, and we see no reason to stray away from this guidance given
the unusual late summer air mass in place.  A quick glance at
climatology confirms that this won`t be record-breaking heat, but
we`re not far from it.

Considerable differences are noted among global guidance by late
next week.  WPC`s Cluster Analysis Tool, which links together
similar solutions, shows about 55% of ensemble members favoring
continued hot and dry conditions into late next week as the ridge
remains positioned over the Southern Plains, while the other 45% of
members favor a cooler and wetter solution with the ridge breaking
down.

&&

.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 622 PM CDT Wed Sep 14 2022

Central Illinois will be on the western periphery of a ridge that
extends from the eastern Great Lakes across the upper Ohio River
Valley. Light and variable winds overnight will be replaced by a
modest south breeze during the day Thursday. Some fog development
may spread south from northern Illinois to near the I-74 corridor
but the chance for vsby impacts on station is too low to include
in the TAF at this time. Otherwise VFR conditions will prevail
through the period with mainly cirrus expected.


&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...Deubelbeiss
SYNOPSIS...MJA
SHORT TERM...Geelhart
LONG TERM...MJA
AVIATION...Deubelbeiss



Area Forecast Discussion

National Weather Service Indianapolis IN

 1154 PM EDT Wed Sep 14 2022

...Updated Aviation Discussion...

.Forecast Update...
Issued at 945 PM EDT Wed Sep 14 2022

Forecast is in good shape this evening, with high pressure remaining
in control. Only expecting a few high clouds tonight, along with
light surface winds.

These conditions will be conducive to fog formation tonight, and
once again some dense fog is possible. By this time last night, some
fog had already formed in Indiana, but nothing is seen in surface
observations at the moment. Hi-res short term guidance has less
coverage of dense fog tonight compared to Tuesday night as well.

Thus, at the moment feel there is no need to issue a Dense Fog
Advisory for later tonight. Will continue with a Special Weather
Statement highlighting the threat for areas of dense fog. Will keep
a close eye on surface obs through the night.

Tweaked low temperatures some based on latest trends, but no
significant changes were made.

&&

.Short Term...(This evening through Thursday)
Issued at 243 PM EDT Wed Sep 14 2022

Highlights...

* Areas of Dense Fog late tonight into tomorrow morning.

* Dry, mostly clear with increasing temperatures

Rest of Today...

The remainder of today will be quiet with near calm conditions. A
1500m saturated layer has developed near the PBL height due to an
elevated subsidence inversion. This has lead to suppressed diurnal
cumulus over most of central Indiana. These scattered clouds will
dissipate quickly this evening as a new inversion develops within
diurnal cooling. Highs will be in the low 80s, dropping steadily
after 4PM into the upper 60s by late this evening.

Tonight and Tomorrow...

The main forecast problem tonight will be the formation of ground
fog as the near surface approaches and reaches saturation. The
formation of diurnal cumulus within strong subsidence this
afternoon hints at an elevated layer of moisture, of which should
limit dry mixing overnight. In return, dewpoints should stay in the
mid to upper 50s throughout central Indiana. A dew point depression
of 20-25 degrees should be easily overcome within efficient diurnal
cooling, leading to a nearly saturated shallow surface layer late
tonight into tomorrow morning. With minimal winds expected, fog
should quickly develop over most of the region. There is still some
uncertainty in the extend and thickness of said fog given subtle
microscale factors, but confidence is increasing on at least patchy
dense fog over all of central Indiana. For now, a SPS will be
utilized to communicate fog potential/impacts, with further analysis
later this evening on if an advisory is needed.

The upper level ridge and high pressure will remain over the Ohio
Valley for tomorrow. The overall airmass looks to be rather similar
with a typical temperature curve, peaking in the low to mid 80s in
the afternoon. Any remaining fog should flush away by 10am tomorrow
morning through PBL expansion and mixing.

Analysis of HRRR integrated smoke indicates an elevated layer of
smoke, trapped within the upper level high, will push into the Ohio
Valley tomorrow. This should have minimal impacts at the surface,
but slightly hazier skies, and an increased sunset spectacle in the
evening are likely.

&&

.Long Term...(Thursday night through Wednesday)
Issued at 243 PM EDT Wed Sep 14 2022

* Above normal temperatures into next week.

* Largely dry except Sunday night into Monday.

Ridging at the surface and aloft will set the stage for broad
southerly/southwesterly low level flow over the weekend into next
week, with a prolonged stretch of above normal temperatures expected
as a result, with highs generally in the 80s each day (with a few
low 90s readings possible), and lows generally in the 60s, save for
tomorrow night when lows in the mid to upper 50s can be expected.

The ridge aloft will gradually deamplify during the period, although
the broad southwest flow will remain in place as it does so. This
will leave the area largely dry throughout the long term portion of
the forecast, save for late in the weekend into early next week.

Deterministic guidance diverges a bit in its placement and intensity
of a broad upper level wave expected to move through the Great Lakes
Sunday night into Monday, and thus can justify no more than chance
pops during this period. Convective indices suggest thunder
potential and will carry this in the grids as well. The system
should be progressive enough to prevent any prolonged rainfall or
significant hydrologic potential, and this likely represents the
only opportunity for rainfall through the seven day forecast.

&&

.Aviation...(06Z TAF Issuance)
Issued at 1154 PM EDT Wed Sep 14 2022

Impacts:

* IFR/LIFR conditions in fog expected early Thursday morning.

Discussion:

GOES16 shows clear skies across the taf sites late this evening.
However, dew point depressions were already approaching 2F or less.
Light to calm winds are expected overnight due to a strong area of
high pressure over Ontario stretching across the Ohio valley to the
deep south. This will result in ideal radiational cooling overnight
and areas of fog will form once again. Fog will be IFR/LIFR and
confidence is higher at LAF/BMG/HUF due to the urban heat island
effects of IND.

VFR will return by mid morning on Thursday as daytime heating
resumes. This will quickly burn off the diurnal fog. The large
surface high pressure system will continue to provide dry weather on
Thursday as forecast soundings continue to indicate a dry column
along with unreachable convective temperatures.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

Update...50
Short Term...Updike
Long Term...Nield
Aviation...Puma



Area Forecast Discussion

National Weather Service Lubbock TX

 623 PM CDT Wed Sep 14 2022

...New AVIATION...

.SHORT TERM...
(This evening through Thursday)
Issued at 139 PM CDT Wed Sep 14 2022

18Z upper air analysis depicts a negatively-tilted trough pivoting
over the Intermountain West with several smaller-scale shortwave
perturbations embedded within the broadly cyclonic flow. Further
east, shortwave ridging continues to translate eastward over the
Osage Plains and into the Ozark Plateau, with the monsoonal fetch
situated between the broad, negatively-tilted trough; and the
departing shortwave ridge. At the surface, a broad moist sector is
in place across the CWA with breezy, southerly winds near 15-25 mph
in response to the sharpening trough located in vicinity of the
Mescalero Escarpment and extending poleward into the Nebraska
Panhandle. There are no fronts or surface cyclone features near the
CWA; however, the presence of the surface trough will serve as a
focus for thunderstorm initiation this afternoon near the Texas/New
Mexico state line as low-level confluence and convergence increases
beneath the ejecting shortwave trough. Moist, isentropic ascent has
contributed to the ongoing showers in the mid-levels which has been
the culprit of the cirrus debris, and shallow, surface-based cumulus
have started to develop over eastern New Mexico as per latest
visible satellite imagery. The expectation is for scattered showers
and thunderstorms to develop near or after 21Z along the surface
trough, with cold pool mergers facilitating perhaps a few broken
lines or clusters surmounted by a well-mixed boundary-layer with PBL
heights nearing 750-700 mb this afternoon. GOES-East Blended Total
Precipitable Water imagery detects a plume of PWATs near 1.20"
advecting northward across the Caprock, which also coincides with
recent RAP analysis estimates. While PWAT content remains below the
99th percentile (as per interpolated 15/00Z climatology from the AMA
and MAF RAOB sites), tall and skinny thermodynamic profiles with
MUCAPE values near 1,500 J/kg west of the I-27/HWY-87 corridors
amidst favorable warm cloud-layer depths will result in heavy
rainfall with the deepest cores, with rain rates potentially
exceeding 1"/hr, especially across the western zones where coverage
of convection is greatest. The strongest cells will also be capable
of producing wind gusts in excess of 50 mph and a rogue, severe-
caliber gust or two cannot be ruled out either but the overall
severe thunderstorm risk is low.

Convection is forecast to decrease in coverage as it nears the I-27
and HWY-87 corridors late this evening as the PBL stabilizes from
the cessation of diabatic heating/vertical mixing, and the potential
for convective wind gusts will decrease thereafter. However, locally
heavy rainfall will be possible through at least midnight before
thunderstorms collapse altogether with residual showers lingering
overnight as additional shortwave perturbations eject overhead and
therefore maintain the moist, isentropic ascent throughout the low-
and mid-level theta surfaces. Similar sensible weather conditions
are expected tomorrow as the airmass remains largely the same
despite the convective overturning, and the thinking is that
thunderstorm coverage will be less (i.e. isolated) as the trough
axes shift eastward (e.g. increasing subsidence) and as high-level
flow becomes less difluent. Low PoPs have been maintained across the
northern South Plains into the extreme southern TX PH as the diffuse
surface trough shifts eastward from its location today.

Sincavage

&&

.LONG TERM...
(Thursday night through next Tuesday)
Issued at 139 PM CDT Wed Sep 14 2022

Convection on Thursday afternoon into the evening is expected to
be much more isolated than today`s anticipated convection. We will
be in the wake of a departing short wave resulting in increasing
subsidence aloft. In addition, very dry air will be advecting into
the area from about 600mb on up. There will be some sharpening of
the surface trough leading to low level convergence mostly on the
caprock. A very narrow corridor of higher theta-e values will
exist along this corridor of weak convergence generating
mixed layer instability values around 500-1000 J/kg. With the very
dry air aloft and a deeply mixed boundary layer, downburst winds
will be a possibility with any isolated convection that does
develop.

For next week, models have quite literally flip flopped in regards
to the position of the eastern CONUS ridge. The ECMWF and its
ensembles want to hold the ridge nearly overhead next week allowing
a fetch of monsoon moisture to stay to the west of the region. The
GFS holds the ridge overhead as well for the first part of the week
and then moves east during the second part of the week. The
corresponding ensembles reflect more of the ECMWF solution holding
the ridge overhead. There may still be hope late next week if the
ridge can move far enough east to allow moisture to stream overhead.
Temperatures will likely stay above seasonal averages through the
next week with this ridge in place. Thickness will rise through the
period keeping temperatures warm until possibly late next week.

&&

.AVIATION...
(00Z TAFS)
Issued at 620 PM CDT Wed Sep 14 2022

First piece of lift and associated showers and thunderstorms a bit
ahead of schedule and have mostly cleared KLBB and KPVW. Dry air
downstream suggest storms may not hold together and reach KCDS.
Meanwhile, the second piece of lift is rotating across eastern New
Mexico with additional showers and thunderstorms developing west
of the terminals. This lift looks to be less focused, so some
questions regarding how widespread they will be. Decided not to
hold onto the vague VCTS wording, but note that there remains a
chance for TS to affect the terminals through the evening despite
no TS mention in the official forecast.

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

SHORT TERM...09
LONG TERM....01
AVIATION...07



Area Forecast Discussion

National Weather Service Missoula MT

 251 PM MDT Wed Sep 14 2022

.DISCUSSION...Satellite loops this afternoon show smoke trapped in
the region and especially trapped in most of the valleys. The
stability caused by the smoke is quite evident when observing how
many of the storms are weakening after moving into Idaho and
northwest Montana.

A low pressure system in northeastern Washington is sending a
spoke of energy into north-central Idaho and western Montana,
resulting in showers and isolated thunderstorms. Convection
allowing models show varying coverage for storms today, and the
lack of warming due to smoke continues to cause decreased
confidence in a more widespread nature of the showers for the
rest of the day.

The HRRR smoke model shows some improvement in the smoke
throughout the region, but also shows that smoke will remain
trapped in most of the valleys. Cloud projections show periods of
decreased cloud cover tonight, but also show increasing cloud
cover from the southwest overnight. Rain amounts this afternoon
and evening and the cloud cover forecast are important aspects of
the fog forecast for tonight and Thursday morning. Places that
have at least some clearing and rain will most likely have a
return of fog, but overall the impact from fog should be less than
this morning.

Another focus for rain is showing up for Thursday, mainly for
points south of I-90, with a mid-level circulation that is
expected to develop in southwest Montana. Thunderstorms are
possible especially where there is less smoke. The strongest
storms have a 10-20 percent probability of producing heavy rain
during Thursday afternoon. Shower and isolated thunderstorm
chances return for Friday.

Model guidance agree on near to below average temperatures during
this weekend, but there is still a big range on how much
precipitation will occur.


&&

.AVIATION...A low pressure system in northeastern Washington is
sending a spoke of energy into north-central Idaho and western
Montana, resulting in showers and isolated thunderstorms. Showers
and thunderstorms will become more widespread through the
afternoon and evening across all of western Montana and central
Idaho. Smoke is expected to remain trapped in the valleys through
tonight, though there may be a slow improvement in visibility
beginning this evening. Fog is expected to return to some of the
valleys tonight through Thursday morning, specifically those that
have less cloud cover and receive moisture, but overall the
impact from fog should be less than this morning.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

$$



Area Forecast Discussion

National Weather Service Reno NV

 139 PM PDT Wed Sep 14 2022

.SYNOPSIS...
The Mosquito Fire smoke will continue to produce smoke and
subsequent air quality impacts through the week. Outside of the
smoke, temperatures are autumn-like with chilly mornings and mild,
typically breezy afternoons. Looking towards the weekend, we`re
keeping an eye on the potential for a windy Saturday and a shower
Sunday and Monday, and maybe some high elevation snow showers too.

&&

.SHORT TERM...

Well, I wish there was good news to share on the smoke front, but
with the increased activity on the Mosquito Fire, there aren`t
many positive things to share. Latest HRRR smoke simulations
push another wave of dense smoke into the Reno/Carson City/Sparks
locales between 4pm and 5pm today. A bit of north flow across
west-central Nevada will transport the smoke across the Basin and
Range overnight with widespread smoke for southern Pershing,
Churchill, and Mineral counties, and possibly into eastern
portions of Mono county as well. Tonight into Thursday will really
`spread the wealth` of the smoke across much of western Nevada
and the eastern Sierra. By Thursday afternoon, west winds may help
to push out some of the smoke from the Basin and Range, but far
western Nevada (Reno, Spark, etc) and the eastern Sierra will
experience little reprieve.

For the latest air quality information check fire.airnow.gov. You can
also refer to your local Air Quality Management Division or the
latest Smoke Outlook Statements from the US Interagency Wildland
Fire Air Quality Response Program which are also available via:
fire.airnow.gov.

So let`s talk about something else! Ignoring the smoke, the
temperatures and winds will be quite standard for this time of
year, with cooler mornings and mild, breezy afternoons. Increasing
dry west to southwest flow across the Sierra and western Nevada is
pushing thunderstorm potential eastward this afternoon and
evening with 10-15% chances of storms for southern Mineral and
across the Basin and Range. -Edan

.LONG TERM (Friday Onward)...

A weak upper short wave will pass east across northern CA/NV on
Friday and bring an increased chance for a shower or even isolated
thunder along the northern Oregon border later that afternoon into
the early evening. Other than a slight enhancement in afternoon
westerly breezes in the north Sierra, this weak wave will pass
mostly unnoticed except for the cooler afternoon highs in the low
80s for lower valley areas with mostly 70s across Sierra
locations.

The next upstream system will be noteworthy and a definite turn-
around from the early September`s record heat. This anomalously
deep short wave trough will drop south offshore the western US
from the northeast Pacific through Saturday before lifting into
the region later this Sunday into Tuesday. The vast majority of
ensemble meteogram simulations project winds increasing to 35-45
mph over the Sierra and far western NV as pressure and thermal
gradients respond to tightening height gradients aloft in the
southwest upper flow. This will bring the potential for immediate
impacts to both fire activity and smoke projections across the
region, especially the Mosquito fire, as well as lake and recreational
activities through the weekend.

Although there is an increased potential for showers and precipitation
over the region, timing and amounts remain the the main points of
uncertainty Sunday through Tuesday. But there is at least a
30-50% chance of a few hundredths of an inch of some sort of
precipitation falling mostly over the Sierra and far-western NV
areas. As snow levels drop into the 8000’-9000’ range, some higher
Sierra ridges could see close to an inch of white stuff adorning
the higher peaks overnight Monday into Tuesday.

One thing is for sure, much cooler more fall-like conditions are on
the way. -Amanda

&&

.AVIATION...

* Most current hi-resolution models continue to show smoke and
  haze from the Mosquito fire affecting both surface and slant-
  range VIS Sierra and far western NV terminal through this
  forecast period. HRRR guidance projects a brief few hours of
  MFVR conditions late this afternoon giving way to thicker smoke
  lowering CIGS/VIS to mostly IFR and below in the vicinity of the
  fire and downwind for terminals north of I-80 during the
  overnight hours tonight into Thursday morning. But timing still
  remains an issue dependent upon on local winds and fire
  activity.

* Terminals to the south will not be spared for long as smoke layers
  wrap around and settle south of US-50 and east of US-95 aft 06Z
  with periods of MVFR conditions in smoke and haze for KCXP and
  KMEV. Further south along US-395 in the eastern Sierra to include
  KMMH will remain unaffected by smoke with VFR conditions
  continuing through the forecast period.

* A slight risk for a thunderstorm or two lingering into the
  evening hours continues in southern Mono County and east of
  US-95 in Churchill/Mineral Counties. Typical zephyr breezes with
  gusts near 20 kt are still expected for terminals near US-395
  through this afternoon, with lighter winds overnight into
  Thursday. -Amanda

&&

.REV Watches/Warnings/Advisories...
NV...None.
CA...None.
&&

$$



Area Forecast Discussion

National Weather Service San Diego CA

 130 PM PDT Wed Sep 14 2022

.SYNOPSIS...
Dry weather will prevail through early next week with mostly below
normal daytime temperatures. Areas of night and morning coastal low
clouds and fog will extend inland across much of the valleys and
occasionally onto the lower coastal mountain slopes. Upper level low
pressure moving to near the West Coast could bring slight cooling
early next week followed by warming the second half of next week
after the low moves inland. Locally gusty west winds will occur at
times in the mountains and deserts through early next week.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

Partly cloudy conditions prevailed with a mix of some lingering
stratus near the coast, some stratocumulus in the valleys and
cumulus in the mountains. It was mild at early afternoon with
temperatures mostly in the 70s to mid 80s west of the mountains with
only lower to mid 90s in the hotter lower desert locations.

We are back in the onshore flow marine-layer pattern, though we had
no strong marine inversion this morning (though there were 2
inversions, one around 1500 feet, the other around 5000 feet MSL).
This is expected to continue, so the marine layer stratus will
likely not be solid the next few days, and the HRRR cloud ceiling
maps confirm this, so some locations even near the coast have
sunshine quick early Thursday morning. Most coastal locations have
hourly NBH 3000-foot or below cloud ceiling probabilities of only 60-
75 0 percent late tonight/early Thu and trending downward from
previous runs. In contrast to earlier this month, high temperatures
will be mostly 5-10 deg F below normal in most areas at least
through early next week, though nighttime temperatures will be near
or slightly above normal, partly assisted by the continued positive
sea surface temperature anomalies in our coastal waters, albeit with
some decline in water temps the past few days.

A large upper low will be somewhere off the California coast this
weekend with tropical moisture flowing north on the east side of the
low. Models/ensembles have some disagreement with timing of the low,
but regardless, impacts here will be minor other than perhaps a
little drop in temperatures early next week and maybe a bit of
drizzle from a deepening marine layer, but the ensembles are
almost all agreeing that little or no precipitation will occur in
our forecast area early next week. Moderate warming will likely
occur after the low passes to the northeast in the middle or, more
likely, the latter part of next week.

&&

.AVIATION...
142010Z...Coast/Valleys...Patches of low clouds with bases 1500-2000
ft MSL impacting KSAN and KCRQ at this hour. Those CIGS could become
SCT for periods of time this afternoon. Low clouds near coast will
begin to increase in coverage after 03Z Thursday and spread up to 25
miles inland overnight into Thursday morning, with similar bases.
Expect local vis 3-5SM on higher coastal terrain. Clearing from
inland to the coast likely 17Z-19Z Thursday.

Mountains/Deserts...SCT-BKN clouds at or abv 10000 feet through this
afternoon.

&&

.MARINE...
No hazardous marine conditions are expected through Sunday.


&&

.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.

&&

$$

PUBLIC...Maxwell
AVIATION/MARINE...PG