Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/13/22
See below for an aviation forecast discussion for the 00Z TAFs.
&&
.SHORT TERM...(This Evening through Tuesday Night)
Issued at 235 PM CDT Mon Sep 12 2022
Smoke continues to push in aloft, following along the upper ridge.
So far, only sites at higher elevation in Montana have reported
reduced visibility with near-surface smoke. Therefore, left out a
mention of smoke and just addressed with higher cloud cover in the
forecast. There has also been some smoke east of the Coteau today
from Canadian fires. The HRRR has been doing very well with the
western smoke but has totally missed the smoke in the east.
At the sfc, low pressure will set up across central SD tonight with
some light southerly breezes already ahead of it. Winds will shift
to the east in the northern part of the forecast area behind the low
pressure trough on Tuesday and become breezy. Dry conditions will
continue through the short term. The main challenge will be
temperatures given the elevated smoke and the placement of the
trough.
.LONG TERM...(Wednesday through Monday)
Issued at 235 PM CDT Mon Sep 12 2022
A surface trough of low pressure will slowly move east through the
region Wednesday and Thursday. Aloft, an upper ridge will be
centered over the Northern Plains on Wednesday, with warm temps
aloft translating to above normal temps at the surface. Upper 80s to
low 90s will be common on Wednesday, along with increasing dewpoints
perhaps into the lower 60s as southerly winds bring in moisture.
Best precip chances look to be Wednesday evening/overnight, then
again on Thursday (eastern areas) with the eastward progression of
the surface trough. Interesting to note that soundings do keep
things fairly dry below 600/700mb depending on location. Models vary
a bit on just how much CAPE moves into the region, but regardless,
it appears we should have at least weak instability so thunderstorms
a possibility as well. Upper pattern then goes southwesterly once
the upper ridge passes. It appears a couple waves of energy will
pass through the region bringing additional chances for
precipitation during the extended period. Temperatures through the
period look to stay mild/warm and above normal, with no threat of
overnight frost.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
Issued at 628 PM CDT Mon Sep 12 2022
Terminals KABR,KATY,KPIR,KMBG
VFR conditions are expected through the next 24 hours. Elevated
smoke will remain over the region through Tuesday afternoon.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...Dorn
SHORT TERM...Wise
LONG TERM...TMT
AVIATION...Dorn
AREA FORECAST DISCUSSION
National Weather Service Eureka CA
249 PM PDT Mon Sep 12 2022
.SYNOPSIS...Temperatures will be near normal or even slightly
below normal across the interior during next few days. Coastal
areas will also see more marine influence with cooler afternoon
temperatures and areas of morning low clouds and fog. Inland areas
will generally see clear skies. Some rain is possible this
weekend.
&&
.DISCUSSION...The frontal boundary has generally moved east of the
area and skies are clearing out. Highs are expected to be mainly
in the 80s today with a few locations near 90. A weak marine
inversion has allowed most of the coastal areas to clear out.
Tonight with the clear skies many of the colder valleys are
expected to see lows in the 40s. Frost is not expected tonight
with dewpoints in the 40s or even low 50s today.
Zonal flow aloft is expected for much of the work week. This is
expected to keep temperatures near or below seasonal normals
across the interior. Night and morning marine clouds are likely,
but with the cooler temperatures aloft the marine inversion is
expected to remain weak and there will likely be some clearing
most afternoons. At this it doesn`t like like there will be any
notable winds for fire weather concerns. Just the typical
afternoon west to northwest breezes. Afternoon RH will generally
over 20 percent with many areas seeing RH over 40 percent. RH
recoveries will be good as well with even the ridges seeing RH
recoveries over 70 percent. Frost is possible mid to late in the
week if the dewpoints drop low enough.
For the weekend and into early next there is a lot of different
possible scenarios. Most of the ensemble solutions indicate there
will be cooler than normal temperatures. There is the potential
for some rain, although the ensemble solutions are showing a wide
range of possible amounts ranging from no rain to over a half inch
at Crescent City. Some of these solutions also favor mountain snow
down to 5,000 or 6,000 feet. For now am favoring the drier
solutions, but this will need to be monitored as it gets closer.
MKK
&&
.AVIATION...Skies started the day with stratus and fog along much of
the coast this morning. With the marine layer depth over 3000 ft,
these clouds extended well inland up the adjacent river valleys.
Clouds have mostly burned off with daytime heating, but clouds over
the coastal waters have expanded again during the early afternoon,
with periods of low ceilings and even some fog continuing at KCEC
and KACV. This has mostly been supported by an onshore component to
the low-level wind flow. This flow is expected to become more
offshore tonight, and this should limit land-based cloud and fog
redevelopment. However, uncertainty is high regarding the strength
and effectiveness of this flow. Have kept the forecast at KUKI VFR,
but there are indications in the latest HRRR guidance that the
marine layer may be deep enough to support at least some scattered
clouds making it into the Russian River Valley from the W late
tonight. Winds will remain light. /SEC
&&
.MARINE...NW winds have increased over portions of the S waters this
afternoon, particularly in the expansion fan downwind from Cape
Mendocino. High resolution guidance indicates that this wind will
gradually diminish again later tonight. Winds will become light
southerly N of Cape Mendocino on Tuesday as low pressure moves S
offshore. Seas will remain at or below 5 feet through much of the
week, gradually building a bit by Friday. Additionally, a southerly
swell of 2 to 3 feet at 13 to 15 seconds will continue through the
period with another, smaller SW swell arriving late Wednesday. /SEC
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
None.
&&
$$
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For forecast zone information
see the forecast zone map online:
https://www.weather.gov/images/eka/zonemap.png
Area Forecast Discussion
National Weather Service Grand Rapids MI
947 PM EDT Mon Sep 12 2022
LATEST UPDATE...
Marine
.DISCUSSION...(This evening through next Monday)
Issued at 316 PM EDT Mon Sep 12 2022
- Cool Into Wednesday / Limited Rainfall
Our rather impressive looking storm system in the visible
satellite images is centered over SE Wisconsin at the surface but
over northern Indiana at mid to high levels. This system has
warped the cold air to the south side of it so it`s cooler over
northern Indiana and northeast Illinois than central Lower
Michigan. The rain shield around the system is falling apart as
it has used up most of the mid level moisture that was lifting
through the occlusion process. Over the next 24 hours this system
slowly move east then shear out and merge with a northern stream
system over NE Canada.
This will keep our area inside the deep cold through Tuesday and
actually into Wednesday morning. Even so, due to all of the
layered clouds associated with this system it will not get overly
cold tonight or tomorrow night (no frost/freeze just yet).
The system has used up most of the moisture it had with it, so
even though we get into what would be the deformation
precipitation band later tonight into Tuesday, I do not expect
much in the way of rainfall. It will be more like light rain
showers or sprinkles.
The upper wave that merges with our current system is currently
over central Canada near Lake Winnipeg. The upper level jet
associated with that stays north of the Canadian boarder tomorrow
into Wednesday. Nonetheless it sends a shallow cold front our way
tomorrow night into early Wednesday. Being shallow and without
much upper level support, all that will do for us is keep us
cooler longer. Wednesday should see more sunshine (jet core north
of us by then) even with that shallow cold front.
- Warming Into Weekend Then More Rainfall
Once that system gets out of the way a complex interaction between
a southern stream system and a much stronger northern stream
system (both currently over the Pacific Ocean) builds an upstream
ridge over the central CONUS by Wednesday into Thursday. The
shallow cool air will keep us cooler Wednesday but by Thursday we
will have enough southerly flow at low to mid levels to bring the
warmer air back.
Each day, into the weekend, starting Wednesday, should be warmer
than the day before it. Highs could be well into the 80s by
Saturday. However that complex interaction of the northern and
southern stream creates a progressive upper level trough that
moves slowly east into the following week. Likely we should stay
in the warm air into at least the middle of next week. However
starting Saturday but it may take until Monday, we will end up
with wiggly front near us bring periods of showers and possibly
thunderstorm. Due to the complex nature of these interacting
systems, it is to hard this point to point point how this will
work out but one way or the other we should have 3 to 5 day with
no rain.
- Recurving Typhoon Means Cooler Later
We now have Typhoon MUIFA in the western Pacific. It is forecast
to recurved into the northern stream Polar Jet by the end of this
week. Typically about a week after that happens we get 3 to 5
days of cold weather (a rossby wave interaction thing). This
would suggest much cooler air by the end of next week. There is
support on both the ECMWF and GFS for this to happen.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 817 PM EDT Mon Sep 12 2022
An upper low spinning east through the Southern Great Lakes will
bring clouds to all of the TAF sites over the next 24 hours. At
this time it appears much of the cloud cover will be VFR. The best
chance at some MVFR ceilings will be on Tuesday between 14Z and
21Z as the back edge of the upper low swings across the area.
These clouds will likely be associated with some lake generated
rain showers that occur late tonight over Lake Michigan. A few
light showers will be possible on Tuesday, although we expect
mainly dry conditions most of the time. Light and variable winds
tonight will become west-northwest at 8-15 knots Tuesday midday
and afternoon.
&&
.MARINE...
Issued at 947 PM EDT Mon Sep 12 2022
Have opted to issue both a Small Craft Advisory and a Beach
Hazards Statement for the entire area on Tuesday. An event similar
to last night`s gale will occur over Lake Michigan late tonight
and on Tuesday. The similarities are that the event is tied to a
compact low that will develop a strong core of wind on its west
side. The high resolution models are in agreement that a core of
wind will develop, but the strength is the question. the FV3 and
the ARW are stronger with the HRRR and 4km NAM being a touch
weaker. This will be a somewhat strange event in that the core of
wind will be off shore. What will develop out of this will be a
swell that propogates into our beaches during the day on Tuesday.
The waves for a time at least will have cleaner looks to them as
they will be coming in at a longer period and without wind to
create wind swept spilling breakers. Bottom line though is that 3
to possibly 6 footers will move into all of our beaches on Tuesday
which will pose a hazard to both small craft and late season
swimmers.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement from 6 AM EDT Tuesday through Tuesday
afternoon for MIZ037-043-050.
Beach Hazards Statement from Tuesday morning through Tuesday
evening for MIZ056-064-071.
LM...Small Craft Advisory from 11 AM to 11 PM EDT Tuesday for
LMZ844>846.
Small Craft Advisory from 6 AM to 6 PM EDT Tuesday for
LMZ847>849.
&&
$$
DISCUSSION...WDM
AVIATION...Duke
MARINE...Duke
Area Forecast Discussion
National Weather Service Gray ME
1035 PM EDT Mon Sep 12 2022
.SYNOPSIS...
Clouds increase through tonight as a low pressure system moves
out of the Great Lakes and into the northeast, which will bring
widespread rain showers and scattered thunderstorms to our area
Tuesday. Showers and storms may produce gusty winds, with
greatest chances of damaging winds over western areas. Downpours
can also be expected with these. This system will be followed
by much cooler and drier conditions for the second half of the
week.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
0235Z Update...
Fog and stratus will begin to develop shortly along the
coastline with KPWM already showing a BKN002 deck developing
overhead. Areas of fog will be spreading from south to north,
similar to the latest HREF solution. It will remain a mild and
muggy night across the region for mid September. Have made minor
adustments to the temperature and dew point grids with this
latest update. Cloud cover remains quite variable as well across
the region with far northern and easternmost areas with mainly
clear skies.
Update...
A few sprinkles are ending in the mountains. Otherwise made
minor updates to the near term portion of the forecast this
evening. Increased the cloud forecast for this evening over the
western portion of the forecast area per latest satellite
imagery and surface observations, albeit, there are significant
breaks in the cloud shield over York County region and portions
of central New Hampshire.
The chances for precipitation will gradually increase later
tonight, mainly over southern New Hampshire per latest HRRR and
NamNest runs. Latest HREF solution continues to show low
cloudiness and fog, mainly over southern areas later tonight.
Prev Disc...
Tonight will be warm and humid, especially for September, with
increasing cloud cover and lowering ceilings. This happens in
response to an incoming low pressure system passing through the
Great Lakes, which sends a warm front (aloft, at least) toward
New England and draws an onshore flow overnight... which will
bring increasing dew points into the waters and southern zones,
in turn increasing likelihood of fog formation. Low temperatures
are forecast to be right around today`s dew points... in the
upper-50s toward the north and into the low- to mid-50s further
south.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
A closed upper level low will swing SW to NE down the lower
Great Lakes/Saint Lawrence Valley Tuesday and Tuesday night,
bringing at least a couple rounds of showers and storms across
New England followed by a westward wind shift amid a drier,
incoming airmass. An initial prefrontal trough brings light
showers through southern zones in the morning, which may not
entirely reach the ground with some dry air yet to erode; it may
also have bearing on how well we destabilize during the
daytime.
The primary wave driving showers and storms crosses into the
Connecticut River Valley around noon, in clusters and single
cells initially but escalating to broken lines through the day
as shear increases. The degree to which we destabilize will
hinge on a couple factors... first, recovery after initial
morning showers but mostly how well a surface warm front can
hold together as it pushes north through southern New England as
the low occludes and draws a stable onshore flow. On the other
hand... ramping up the triple point low, which will be aided by
the usual coastal amplification we typically see in this set up,
increases low-level helicity.
So, overall, for hazards... am expecting gusty winds with
showers and storms given the strong wind fields, but locally
damaging winds are possible where destabilization can be
realized considering marginally supportive mid- and low-level
lapse rates. This is most likely across the Connecticut River
Valley and toward the Lakes region of New Hampshire. Hail is
less of a threat... given deep warm clouds depth and unfavorable
lapse rates above freezing. With deep warm cloud depths and
increasing PWATs will come a threat for downpours/locally heavy
rainfall in stronger cells. Lastly... the triple point low does
leave a threat for brief spin-ups / weak tornadoes, but this
would be a low-end threat, limited to southern most zones with
the warm front expected to poke just into our area before being
overtaken by the occlusion.
The dry slot moves in behind the wave of storms during the
evening, clearing southern New Hampshire by around 8-10 PM and
through SW Maine by around midnight. Off-and-on showers will
continue over the northern zones through the night as the mid-
level circulation spins, and upslope flow increases. Elsewhere,
west winds will increase to a breeze... which should prevent
decoupling and widespread fog formation. Fog will likely however
linger over the Midcoast of Maine through late in the night as
the front struggles to mix through the surface. Lows should cool
into the 50s, except closer to 60 near the Midcoast.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
The cold front will continue pushing well to our east during the day
on Wednesday as the 500 mb trough and attendant surface low trek up
the St. Lawrence River Valley, putting New England in a deep layer
of west to northwest flow. This will dry out the mid and upper
levels, but enough low-level moisture will be around for more cloud
cover and scattered upslope showers to continue across the mountains
through most of Wednesday and into the early portions of Wednesday
night before a vigorous shortwave sends a strong but dry cold front
through New England, bringing in a much cooler and drier airmass.
With the NW flow holding off the sea breeze, we`ll see the warmer
temps of around 80 degrees closer to the coast, gradually tapering
off to the mid 70s a little farther inland for Wednesday`s highs.
Toward the mountains, more cloud cover/showers should hold highs to
the 60s. Temps will be much cooler Wednesday night with most seeing
upper 40s to lower 50s, but we could see temperatures in the upper
30s to low 40s across northern areas.
Very dry air will settle over the area for Thurs-Fri, and we`ll be
in a cold air advection pattern with a brisk NW flow. This will
limit high temperatures to the mid-upper 60s across southern areas
and upper 50s to lower 60s across the north despite plenty of
sunshine. We should have no problem mixing down the higher winds and
drier air from aloft during the afternoon hours, so have gone lower
than the NBM guidance on dewpoints as it is typically way too high
in these situations. Forecast soundings also support wind gusts of
around 25 to perhaps 30 mph each day. Thursday night will be on the
chilly side with temperatures in the 40s for the southern half of
the area, but northern areas are expected to have temperatures in
the 30s, and there could be some frost if winds can drop off enough.
Temperatures will follow a moderating trend over the upcoming
weekend as the wind profile becomes southwesterly with high pressure
becoming centered south of the area. The airmass will too dry to
support any precip on Saturday, but by Sunday increasing moisture
and some passing disturbances aloft will bring a return to
showers in the forecast.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
Short Term...VFR continues for today into tonight with light
flow. Restrictions will start to creep into terminals late
tonight in the form of low ceilings, starting in the south and
along the coast during the pre-dawn hours and spreading
inland/northward through the day. Significant restrictions may
lift to MVFR or VFR for a time after dawn for northern and
central terminals, but SHRA coming across later in the morning
and through the day will bring low ceilings yet again with a
chance for gusty winds and TSRA. Conditions begin to improve
behind the primary wave during the evening, with steady
improvement to VFR overnight with wind staving off significant
fog or low ceilings.
Long Term...A few showers along with some MVFR ceilings are
possible toward HIE on Wednesday, but otherwise VFR expected at
all other sites along with winds gusting to around 20-25 kt.
Breezy conditions continue into Thurs-Fri along with VFR
conditions into the upcoming weekend. We could start seeing some
valley fog returning by Thursday night or Friday night toward
HIE and LEB if winds drop off enough.
&&
.MARINE...
Short Term...Light southerly flow today turns onshore tomorrow
with an area of low pressure approached from inland... bringing
showers and fog to the waters tomorrow and tomorrow night.
Conditions are expected to remain below SCA thresholds during
this time, however locally stronger gusts in thunderstorms are
possible during the late afternoon and evening. Winds turn to
the west tomorrow night, and will be trending stronger into
early Wednesday.
Long Term...Conditions may reach SCA levels on Wednesday with west
to southwest winds possibly reaching 25 kt. After, a dry cold front
will quickly push across the waters Wednesday night with brisk
northwest winds gusting to around 25 kt through Friday, likely
requiring a SCA. Improvement is expected by late in the day Friday
or Friday night with conditions forecast to remain below SCA
levels into the weekend.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.
&&
$$
NEAR/SHORT TERM...Cannon
LONG TERM...Combs
Area Forecast Discussion
National Weather Service Wilmington NC
718 PM EDT Mon Sep 12 2022
.SYNOPSIS...
After a muggy night tonight, less humid air will start pushing
into the region following a cold front on Tuesday. High pressure
remaining to our north will keep the weather dry and seasonable
for several days thereafter.
&&
.UPDATE...
Convection has been fairly underwhelming so far, although there
still are a couple of hours to go with moderate confidence for
some impacts on the I-95 corridor. I`ve blended in the latest
HRRR and RAP hourly PoPs into our gridded forecasts which yields
20-30 percent coverage tonight, except locally higher across
portions of Robeson and Darlington counties before 9 pm. Despite
CAPE near 2000 J/kg and effective bulk shear near 30 knots,
poor lapse rates and few surface boundaries are limiting how
much convective coverage we`ve got. The surface cold front is
still anticipated to make it almost down to the coast by
sunrise. Changes with this update centered on PoPs and sky
cover.
&&
.NEAR TERM /THROUGH TUESDAY/...
A cold front entering the western Carolinas will move to the coast
by sunrise Tuesday and shift farther offshore through then end of
Tuesday.
Early indications of the instabilities are coming to fruition with
mixed layer CAPE between 1800 and 2200 J/Kg. The upper-level forcing
is very weak in the southwesterly flow aloft. The effective shear
over the northern half of the CWA is around 30 knots. Thus the
marginal risk. The convection has struggled to develop this
afternoon with a couple of convective elements along the coast near
MYR and up the coast.
The HRRR continues to be very generous creating convection over the
next few hours. There is a hint of a slight increase in the showers
and thunderstorms over the past hour. Thus will keep a higher chance
of PoPs along the coast.
On Tuesday, as the front shifts off the coast drier air will push
across the area with only a slight chance of a shower along the
coast of Southeast North Carolina earlier in the day.
Low temperatures tonight will range from the upper 60s inland to the
lower to middle 70s at the beaches. Highs on Tuesday will be cooler
to the west with the front moving off the coast. Temperatures will
only reach the mid 80s inland and upper 80s along the coast away
from the beaches.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
Deep layer moisture will be offshore through the period keeping the
area rain-free even though mid level trough axis swings through.
Surface high pressure well to our north will be slowly progressing
eastward. Temperatures will be fairly close to climatology but the
humidity will be much noticeably lower than the past several days
compliments of the northerly component of the wind.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
Trough axis to our east on Thursday and the surface high to our
north weakens but we appear to keep a light northerly wind component
for a continuation of fairly comfortable dewpoints in the low 60s.
This stretch of quiet weather is shaping up to be long-lived. An
upper level ridge builds to our west and a moderately strong trough
develops off of the New England Coast, the latter pushing higher
surface pressures in from the north once again. The GFS is holding
its ground that a late week coastal low develops but it also
continues to be the unsupported solution.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
A surface cold front will slowly move eastward and will approach
the coast Tuesday morning. Convective clusters ahead of the
front have a moderate potential to impact KLBT before 02z, and a
low potential elsewhere. VCTS/VCSH forecasts in the latest TAF
set indicate this potential. Generally dry weather and VFR
conditions should develop after 05-07z with only a low to
moderate potential for some MVFR ground fog developing at inland
airports before daybreak. Dry westerly winds should occur during
the day Tuesday with VFR conditions continuing.
Extended Outlook...Drier air will make it to the area Tuesday
night through Friday with little convection and a high
likelihood of sustained VFR conditions. Possible MVFR/IFR
conditions from showers and thunderstorms may occur on Saturday.
&&
.MARINE...
Through Tuesday...A cold front moving into the western
Carolinas will shift to the coast and slowly shift offshore by
the end of Tuesday. The winds will be from the southwest around
15 knots and veer to the west at 10 knots by late in the day. On
Tuesday, the dominant wave height will be 3 to 4 feet and
subside to 2 to 3 feet on Tuesday. The easterly swell of 13 to
14 seconds will continue to diminish very slowly through the
next day and this is reflected in the subsiding seas of 2 to 3
feet.
Tuesday night through Saturday...Not the most common wind direction
through the period; generally out of the northeast. High pressure to
our north following Tuesday FROPA being the main reason. Later in the
period the high gets reinforced by an upper low off the New England
Coast. Waves will gradually grow in height the entire period as the
long fetch remains established and swells build but they will
generally remain below advisory thresholds.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...High Rip Current Risk until 8 PM EDT this evening for NCZ106-
108.
MARINE...None.
&&
$$
SYNOPSIS...ILM
UPDATE...TRA/RH
NEAR TERM...RH
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...TRA
MARINE...ILM
...UPDATED AVIATION FORECAST DISCUSSION...
.SHORT TERM...(This evening through Tuesday night)
Issued at 255 PM CDT Mon Sep 12 2022
The main concern in the short term will be highs
Tuesday and smoke potential this evening into Tuesday from the
wildfires in the northwest CONUS. Did keep sky cover between 30 and
40 percent to account for some elevated smoke through Tuesday
afternoon. Expanded the coverage from inherited forecast to account
for the smoke making it farther south into portions of southwest
Nebraska Tuesday. The HRRR integrated vertical smoke shows a plume
of elevated smoke rotating southward from South Dakota into Nebraska
and dispersing a little as it does, so there might not be a
significant amount of elevated smoke. As for seeing any smoke at the
sfc, it looks less likely at the moment, the HRRR near sfc smoke
model really backs off sfc smoke moving into the area this evening
and overnight, so confidence is low in any reduced visibility from
haze or smoke at the sfc.
As for temperatures on Tuesday, they will be the warmest
temperatures through the end of the work week. The upper level ridge
will nearly be centered over the High Plains. 850 temps around 25
to 29C combined with southerly winds should give just enough
mixing in the afternoon for highs to reach the 90s, with mid to
upper 90s across southwest Nebraska. Did trend with the warmer
bias models of the MET and 90th percentile as confidence grows in
warmer temperatures for Tuesday. In comparison with climate for
this time of year, highs in the 90s are around 15 to 20 degrees
above normal.
There will also be an elevated concern for fire weather with the
combination of the above normal temperatures and min RH ranging from
around 10 to 20 percent for western and southwest Nebraska,
including all of the Sandhills. SFC winds of 5 to 10 mph tomorrow,
were the main reason for not putting out headlines. Confidence is
moderate that sustained winds won`t exceed much past 10 mph
throughout the day, supported by bufkit soundings where much of the
winds in the lowest levels are below 10 kts. Any stronger winds, 15
kts or so, are at 700 mb or higher. The environment does not support
deep mixing so it is very unlikely any of the "stronger" winds would
make it to the sfc.
.LONG TERM...(Wednesday through Monday)
Issued at 255 PM CDT Mon Sep 12 2022
A trof begins to move eastward into the High Plains Wednesday
night bringing the next chance for precipitation. At this time
precipitation amounts will generally be fairly light, generally
less than 0.10 of an inch, however there could be a narrow
corridor of amounts greater than 0.10 but generally all amounts
should be less than a quarter of inch. Temperatures will cool
slightly after Wednesday with highs generally in the 80s through
Saturday. Looking ahead, confidence is increasing in the
possibility of seeing a return to well above normal temperatures
next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 625 PM CDT Mon Sep 12 2022
VFR conditions expected to prevail through tomorrow evening. A
weak frontal boundary slides into the Sandhills tonight, leading
to a wind shift from southerly to northerly across northern
Nebraska. Further south, winds should remain southerly through the
day tomorrow, at around 5 to 10kts. Smoke filters into the area
aloft, though no surface impacts are expected.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gomez
LONG TERM...Gomez
AVIATION...Brown
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1057 PM CDT Mon Sep 12 2022
.UPDATE...
Issued at 1056 PM CDT Mon Sep 12 2022
Updated to include 06z aviation discussion below.
&&
.DISCUSSION...(This evening through Monday)
Issued at 306 PM CDT Mon Sep 12 2022
KEY MESSAGES:
- Dry weather through Wednesday, followed by warmer and more humid
conditions and several small chances for showers and thunderstorms
through the weekend.
Today through Wednesday... Quiet weather is expected to prevail
through mid week with a surface high dominating the pattern across
the central US. The upper low spinning over the Great Lakes has
worked to bring smoke aloft southward across western Minnesota. The
HRRR has had a hard time capturing this today, so went ahead and add
in some smoke/haze through this evening. Heading into Tuesday,
additional smoke looks to move in from the west so kept widespread
haze. We`ll begin to see a shift in our cool, dry pattern towards a
warmer and more unsettled one with a surface low developing over the
Dakotas Wednesday. Southerly flow will advect warm moisture northward
Wednesday with dew points creeping up into the upper 50s and low 60s
and temperatures in the mid 80s along the Buffalo Ridge and upper
70s/low 80s elsewhere.
Wednesday night through Friday... Our first precip chances make an
appearance overnight Wednesday as the warm front moves into central
Minnesota. A LLJ will help ramp up rainfall and thunderstorm chances
into early Thursday morning. Scattered showers and thunderstorms
associated with the warm front and approaching surface low are
possible throughout the remainder of the week. While the showers
will be widespread, we`re not looking at much in the way of QPF with
less than a tenth of an inch for the majority of the CWA and
slightly higher amounts along the far northern areas. Latest
guidance has shifted the area of heaviest rainfall a little further
north across northern Minnesota closer to the center of the low. QPF
amounts over the two day period have also been nudged up a bit, but
the biggest changes lie outside of the CWA.
Saturday through Monday... Additional chances for showers and
thunderstorms hang around through the weekend as a couple weak
shortwaves move across the region. Winds remain light and southerly
from Friday night onward, keeping dew points in the low to mid 60s.
Forecast pwats look to be around 1.5" Sunday, which is near the top
of the climatological max for mid September. Additional rainfall
totals of up to 0.25" are possible through Monday. Looking ahead,
our warmer and wetter than normal pattern will likely continue into
early next week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1056 PM CDT Mon Sep 12 2022
Solid VFR conditions throughout this TAF set. Passing FEW-SCT high
cirrus clouds and haze from smoke well aloft. Winds will remain under
10kt, with varying directions as the center of high pressure shifts
away from the area and a dry cold front approaches from the north
late tomorrow.
KMSP...No additional concerns.
/OUTLOOK FOR KMSP/
Wed...VFR. Wind SE 5-10 kts.
Thu...Mainly VFR. Chc -SHRA/-TSRA. Wind S 10-15 kts.
Fri...Mainly VFR. Chc -SHRA/-TSRA. Wind S 10 kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&
$$
UPDATE...JPC
DISCUSSION...Dye
AVIATION...JPC
Area Forecast Discussion
National Weather Service Reno NV
1258 PM PDT Mon Sep 12 2022
.SYNOPSIS...
Haze and smoke from the Mosquito Fire will continue across much of
the region this week with continued west southwest flow. Showers and
thunderstorms are forecast through Tuesday, then drier air works
into the region resulting in more isolated shower potential.
Temperatures will be near to below normal, with freezes likely in
mountain valleys each morning. There`s potential for an early
season cold front with showers late Saturday into Sunday.
&&
.SHORT TERM (through Tuesday)...
* With a moist and moderately unstable airmass, showers and
thunderstorms will remain likely this afternoon and evening.
Latest HREF models are showing potential for overnight showers and
a few storms as well, lingering into Tuesday morning. Typical t-
storm impacts can be expected: locally heavy rains of 1-2", strong
outflow winds to 50 mph with blowing dust/smoke, and lightning.
Into Tuesday afternoon, guidance indicating best chances for
storms shift eastward as drier air works in from the W/NW. Mono-
Mineral Counties up into areas near and east of Fallon.
* Smoke from the Mosquito Fire is of course the other big weather
factor. T-storm outflows will complicate smoke movement over the
next 24-36 hours, so while the HRRR Smoke model has done well
lately, forecast uncertainty is higher due to these outflows.
Still looks like areas along I-80 and Hwy 50 corridors have
highest risk of smoke impacts to air quality and visibility.
-Chris
.LONG TERM (Wednesday and beyond)...
TEMPS: We are settling into a seasonable stretch of temperatures,
with highs hovering at or just above average for mid-September.
Western Nevada lower valleys will see low 80s to upper 70s, while
Sierra communities will range in the 60s and low 50s. A system looks
to enter the picture by the end of the week, giving us a shot at
some sub-seasonal temperatures to begin the next week with. Of
course with any long range modeling there is a bit of uncertainty,
but as of now there is potential for Sierra valleys to see some
temperatures at or near freezing early next week.
PRECIP: For Wednesday into Wednesday evening, areas such as
Mineral/Churchill/Pershing counties and points eastward have the
best chances for rainfall as resident moisture exits to our east.
Things dry out by Thursday, as we return to a more typical weather
pattern, even though it could be brief. The weekend brings us
chances for precipitation over NW Nevada and N California as the
next trough approaches the area. Just how far south this moisture
may get is still to be determined, as are the amounts. We may just
get the winds instead...
WINDS: We will see the return of the afternoon zephyr breezes with
gusts 20-25 mph through the bulk of the week. An incoming trough
late week may modify our winds to become a more westerly direction,
and look to be on the order of 25-35 mph for gusts in lower valleys.
Current ensembles bring stronger winds in for Sunday, and Sierra
ridges near Tahoe could see gusts up to 60 mph. Winds taper off into
early next week.
SMOKE?: Smoke modeling is dependent upon many things, but fire
behavior is one we cannot easily predict. Should the fire receive
rainfall today, the outlook would be much different than if it were
to keep burning at the rate it has been. We can predict winds which
would transport the smoke, but modeling just how much smoke is being
produced at long range time frames is less predictable. -HRICH
&&
.AVIATION...
* Smoke from the Mosquito Fire will continue to limit visibility for
many areas through Tuesday with prevailing W/SW flow. Widespread
haze with 6-10 mile visibility forecast with a zone of high risk
for 1-3 miles from TRK/TVL over into RNO/CXP/MEV and possibly NFL.
HRRR Smoke model is showing some cleaner air working in from the
S/SW tonight into Tuesday morning, possibly as the result of
convective outflows, so trends toward VFR are possible for
TVL/MEV/CXP and maybe further north towards RNO too. Areas to the
north and south including MMH and SVE look to remain out of the
thick smoke, but mountain obscuration in haze remains likely.
* Showers and t-storms are a good bet this afternoon, continuing
into the overnight hours, with a moist and moderately unstable
airmass overhead. 50-70% chance of seeing impacts from t-storms at
any given point: MVFR-IFR conditions in heavy rain showers &
dust/smoke, outflow wind gusts to 45 knots, and lightning. Smoke
will obscure Cu/Cb development so storms may catch some off-guard.
Main storm risk shifts a little eastward Tuesday, with areas such
as MMH, HRH, NFL have 40-60% chance of seeing t-storm impacts.
-Chris
&&
.REV Watches/Warnings/Advisories...
NV...None.
CA...None.
&&
$$