Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/29/23
Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
709 PM MDT Mon Aug 28 2023
...New AVIATION...
.SYNOPSIS...
Issued at 222 PM MDT Mon Aug 28 2023
Scattered to numerous storms across eastern New Mexico will persist
during the overnight hours, gradually winding down closer to sunrise
Tuesday morning. Storm coverage drops Tuesday, compared to prior
days, thanks to slightly drier air filtering in from the north and
high pressure beginning to slide back east. Some isolated to
scattered storms are possible across the southwest and central
mountain chain drifting south. High pressure moves overhead late
Wednesday early Thursday with isolated high terrain storms during
the afternoon. High pressure shifts east of New Mexico late
Thursday and Friday as some monsoon moisture trying to clip
western NM, while central and eastern NM remaining mainly dry.
Meager monsoon moisture will provide some late day isolated
showers and storm across western and far northern NM this weekend
ahead of a storm system over the intermountain west. Drier
westerly flow overtakes the region by Monday. Temperatures will be
at to a few degrees normal, especially across the east, through
tomorrow before warming up to around 5 to 10 degrees above normal
late week into next weekend.
&&
.SHORT TERM...
(This evening through Tuesday night)
Issued at 222 PM MDT Mon Aug 28 2023
A few showers persisted over southeast NM early this morning with
some lower clouds along the east slopes of the central mountain
chain and into eastern NM. So far this afternoon, showers and storms
have been concentrated over north central NM as well as south of the
ABQ CWA. CAMS continue to suggest storms currently over and along
the east slopes of the Sangre de Cristo mountains will propagate
south and southeastward later this afternoon and this evening along
the east slopes of the central mountain chain and adjacent portions
of the eastern plains, although models don`t focus the heaviest
precipitation so far to the east, for the most part it stays along
and west of the Pecos Valley. Consequently, an east wind into the
RGV at KSAF and KABQ, appears inevitable late this afternoon or
early this evening, possibly gusting to around 40 mph at KABQ. The
latest HRRR now has a second batch of showers developing over
northeast NM later this evening which also tracks southward so at
least some showers will continue after midnight along the central
mountain chain eastward.
Tuesday and Tuesday night will be less active as the upper high
center moves eastward and into NM. Showers and storms will be
focused over the higher terrain and move to the south or even
southwest, so less likely to stray very far from the mountains.
Highs Tuesday will be a little cooler than today`s and a few degrees
below normal over the east.
&&
.LONG TERM...
(Wednesday through Sunday)
Issued at 222 PM MDT Mon Aug 28 2023
A fairly dry and hot long term period is expected, especially across
central and eastern NM. The 594 dm upper level high continues it`s
trek east Wednesday, ending up over the NM/AZ border late in the
day. Temperatures will warm up to near average across eastern and
central areas to around 4 to 8 degrees above average across western
areas. Dry north and northeasterly flow will allow PWATs to continue
to drop, to around 0.50 to 0.75 inches areawide, resulting in just
an isolated coverage of storms across the southwest mountains.
The 592 dm high moves overhead Thursday morning east towards eastern
NM and the TX panhandle late in the day in response to an upper low
approaching the Pacific NW. This will warm temperatures across
central and eastern NM to 6 to 10 degrees above average. Monsoon
moisture of PWATs between 0.75 to just under 1 inch looks to return
to parts of western NM late Thursday resulting in some isolated
storms across the western high terrain. Friday will be pretty
similar to Thursday, outside of areas along and west of the central
mountain chain being a degree or two cooler, due to a little more
cloud cover from being on the eastern fringe of the monsoon moisture
plume over AZ. This monsoon plume over Arizona will be ahead of a
567 dm upper low, diving south and spinning over the Oregon and
Northern CA coast. Dry air will remain over eastern and parts of
central NM, thanks to southeasterly flow between the broad 595 dm
upper high over the central US and a newly developed upper low over
east TX.
The upper low moves southeast over the Great Basin Saturday,
shifting the weakening monsoon moisture plume more over the AZ/NM
border. The GFS depicts a little midlevel moisture compared to the
ECMWF with this monsoon plume and thus have slightly higher PWATS of
an inch compared to closer to 0.75 inches, according to the ECMWF.
Kept PoPs towards drier solutions with only an isolated to possibly
scattered coverage across the western and far northern high terrain,
given the position of the upper level low. The monsoon plume thins
out Sunday as it moves across northern NM with only an isolated
coverage of showers and storms across the northern and high terrain.
Dry westerly flow with PWATs under 0.50 inches overtakes the entire
state on Labor Day as the upper low opens up and moves northeast
over the northern and central Rockies. During the Labor Day holiday
weekend, high temperatures will be near to a degree or two below
average across western areas and around 3 to 8 degrees above average
across eastern areas. Overnight temperatures will be slightly above
average.
&&
.AVIATION...
(00Z TAFS)
Issued at 704 PM MDT Mon Aug 28 2023
Ongoing convection will persist across the central mts and ewd
through the evening, becoming less robust with loss of daytime
heating. A cluster of tstms will push swd across the ern plains
through 29/07Z capable of lcl heavy rainfall, frequent lightning,
and gusty outflow winds. Convectively aided east winds will
continue through the evening hours at KABQ, with gusts to 35 kts
commonplace. While gusts will taper off aft 29/047Z, ely component
of the wind will persist until morning. MVFR cigs will return
along the central mts, improving aft sunrise. Drier air will work
its way into the area tomorrow but sct shwrs and tstms will remain
possible in the aftn.
&&
.FIRE WEATHER...
Issued at 222 PM MDT Mon Aug 28 2023
Scattered to numerous showers and thunderstorms, some with locally
heavy rain, will impact north central NM as well as the central
mountain chain across eastern NM this afternoon and tonight.
Isolated activity expected west of the Rio Grande Valley. Cell
motion will be to the southeast and south. Shower and storm chances
taper down on Tuesday as upper level high pressure starts to move
eastward and back over NM where it will reside Wednesday into
Saturday. Some moisture will linger though for isolated to scattered
showers and storms focused over the northern and western high
terrain Wednesday through Friday. The monsoon plume of moisture will
sharpen over eastern AZ and western NM Saturday but will be sheared
apart on Sunday as an stronger upper trough passes through the Great
Basin and CO Sunday/Monday, bringing drier air and some westerly
breezes next Monday. Temperatures will be near to above normal while
humidities trend somewhat drier but generally don`t reach critical
thresholds.
Areas of fair to poor ventilation rates are forecast Tuesday
through Thursday with good to excellent rates forecast Friday.
&&
.PRELIMINARY POINT TEMPS/POPS...
Farmington...................... 61 91 62 95 / 0 0 0 0
Dulce........................... 48 86 50 88 / 10 10 5 10
Cuba............................ 53 83 54 85 / 20 10 5 10
Gallup.......................... 53 89 55 92 / 0 5 5 10
El Morro........................ 52 83 53 86 / 5 10 5 30
Grants.......................... 53 86 53 89 / 5 10 5 20
Quemado......................... 54 86 56 87 / 10 20 10 40
Magdalena....................... 58 82 58 85 / 30 20 20 30
Datil........................... 54 81 55 84 / 20 20 20 40
Reserve......................... 57 89 58 89 / 10 20 20 40
Glenwood........................ 65 92 64 91 / 20 30 20 50
Chama........................... 45 79 46 82 / 30 20 10 20
Los Alamos...................... 56 80 56 84 / 40 40 10 20
Pecos........................... 54 76 53 83 / 60 50 20 10
Cerro/Questa.................... 45 78 44 82 / 40 30 10 20
Red River....................... 41 71 40 75 / 50 40 10 20
Angel Fire...................... 40 70 37 76 / 50 50 10 20
Taos............................ 49 80 49 85 / 40 20 10 10
Mora............................ 49 73 47 80 / 60 50 20 20
Espanola........................ 53 85 53 90 / 40 20 10 10
Santa Fe........................ 56 80 56 86 / 50 30 10 10
Santa Fe Airport................ 57 82 56 89 / 40 20 5 5
Albuquerque Foothills........... 62 84 62 91 / 30 20 10 5
Albuquerque Heights............. 65 86 64 92 / 30 10 5 5
Albuquerque Valley.............. 60 88 60 94 / 30 10 5 5
Albuquerque West Mesa........... 64 87 63 92 / 30 10 5 5
Belen........................... 65 89 64 93 / 20 10 5 5
Bernalillo...................... 62 88 61 93 / 30 10 5 5
Bosque Farms.................... 62 88 61 93 / 30 10 10 5
Corrales........................ 62 88 62 93 / 30 10 5 5
Los Lunas....................... 63 88 63 93 / 30 10 5 5
Placitas........................ 61 84 60 91 / 40 20 5 5
Rio Rancho...................... 63 86 62 92 / 30 10 5 5
Socorro......................... 64 89 64 94 / 20 10 10 10
Sandia Park/Cedar Crest......... 56 78 56 82 / 40 30 10 10
Tijeras......................... 58 80 58 86 / 40 20 10 10
Edgewood........................ 56 79 55 86 / 50 30 10 10
Moriarty/Estancia............... 55 80 53 87 / 50 30 10 5
Clines Corners.................. 54 76 53 83 / 50 40 20 5
Mountainair..................... 56 79 55 84 / 40 20 10 10
Gran Quivira.................... 57 80 56 84 / 40 30 20 10
Carrizozo....................... 61 82 60 86 / 50 30 20 10
Ruidoso......................... 55 74 54 78 / 60 40 30 20
Capulin......................... 52 74 51 82 / 60 20 5 5
Raton........................... 53 79 51 88 / 60 30 10 10
Springer........................ 52 77 52 89 / 50 30 10 10
Las Vegas....................... 52 75 50 84 / 60 50 20 10
Clayton......................... 59 82 57 89 / 50 10 5 0
Roy............................. 56 78 54 84 / 60 30 10 5
Conchas......................... 60 82 58 91 / 70 20 10 0
Santa Rosa...................... 62 82 60 89 / 70 30 10 0
Tucumcari....................... 62 86 60 93 / 60 20 5 0
Clovis.......................... 62 85 60 91 / 50 20 10 0
Portales........................ 63 87 61 92 / 40 20 10 0
Fort Sumner..................... 63 86 62 90 / 70 20 10 0
Roswell......................... 67 90 66 95 / 60 30 10 0
Picacho......................... 61 81 60 86 / 60 30 20 10
Elk............................. 57 78 56 83 / 50 40 20 10
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
Flood Watch until 9 PM MDT this evening for NMZ211-214-215-226.
&&
$$
SHORT TERM...99
LONG TERM....71
AVIATION...12
See below for an aviation forecast discussion for the 00Z TAFs.
&&
.SHORT TERM...(This Evening through Tuesday Night)
Issued at 310 PM CDT Mon Aug 28 2023
Satellite imagery shows smoke aloft entering northern SD, with
plenty more upstream across ND into southern Canada. That will be
the main forecast issue in the short term. Adjusted sky grids to
better align with HRRR/RAP smoke aloft concentrations. On Tuesday,
these models suggest some potential for surface-based smoke, so went
ahead and added "patchy" smoke to the forecast Tuesday into Tuesday
night. Tough to say if concentrations will be enough to get
visibility down to 6SM or less, so stuck with the "patchy" wording
for the time being. Looking at obs upstream, and there are a few at
6SM and 4SM in northeast MT and southern Canada, with just a
sprinkling of obs across ND less than 10SM, but greater than 5-6SM.
Otherwise, surface flow will remain north/northwest tonight into
Tuesday, with wind speeds Tuesday afternoon fairly similar to what
we saw today. Also, very little change noted in 850mb temps when
comparing this afternoon to Tuesday afternoon. So, expect highs
tomorrow to be within a few degrees of today`s highs. Dry conditions
are also expected through the short term period.
.LONG TERM...(Wednesday through Monday)
Issued at 310 PM CDT Mon Aug 28 2023
Wednesday morning starts with a ridge over the region and a low
moving east from the Pac NW. While the center of the low doesn`t
pass directly over our area, we will still get some troughing and a
cold front, although precipitation looks unlikely at this time. In
fact, precipitation is unlikely until the end of the period. Once
the low moves off to the east Friday, we return to a ridge pattern.
The axis of the ridge remains tilted to the west keeping a westerly
component to the upper level winds, while the lower level winds
remain more easterly, both keeping WAA to a minimum. Saturday
evening and into Sunday morning, winds become more southerly making
for more prolonged period of WAA. As a result, Sunday looks to be
the warmest day of the period for now. Monday morning, a shortwave
looks to pass through the ridge and bring some slight chances
(between 15 and 20 percent) for some precipitation to our west river
counties and spreads through the rest of the area during the
afternoon. Confidence here is low since this is so far out in the
forecast.
The HRRR Smoke model is showing a significant amount of near surface
and elevated smoke for Wednesday. Visibilities are forecast to be
reduced to around 5 miles. This could reduce further with more model
runs. Temperatures seem rather unaffected by the wind shift from the
low passing to our north, keeping pretty steadily in the 80s and
90s. As mentioned before, winds will be shifting directions during
the latter half of the work week with that cold front passing
through. Trended down winds a bit, but they will still be strong
with gusts close to 40 mph starting west river Wednesday morning and
moving east through the overnight hours and into Thursday before
decreasing Thursday night.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
Issued at 546 PM CDT Mon Aug 28 2023
Terminals KABR,KATY,KPIR,KMBG
VFR conditions are currently forecast through the TAF period. A
layer of smoke aloft in the region if forecast to linger into
Tuesday night. Kept the mention of a "cloud layer" aloft going for
this. Watching for the potential that smoke could become surface
based on Tuesday. Have introduced some 6sm FU very preliminarily,
but MVFR VSBY is not out of the question if this materializes.
Will continue to monitor heading into Tuesday.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...Dorn
SHORT TERM...TMT
LONG TERM...KK
AVIATION...Dorn
Area Forecast Discussion
National Weather Service La Crosse WI
1049 PM CDT Mon Aug 28 2023
.DISCUSSION...(This evening through Monday)
Issued at 304 PM CDT Mon Aug 28 2023
Key Messages:
- Isolated shower chances (20-50%, highest along and north of I-
94) north of I-90 this evening and overnight.
- Another hot, dry stretch is increasingly likely with
temperatures building into Labor Day weekend and beyond.
THIS EVENING/OVERNIGHT:
Shower chances will increase later this afternoon as a cold front
ahead of an associated upper-level trough will progress through our
region late this evening and overnight. Generally speaking, the
environment ahead of the front is unimpressive with very skinny CAPE
(100-250 J/kg) and minimal moisture to work with as shown in the
28.12z RAP. However, with some forcing along the boundary and
marginal instability to work with, some transient showers could pop
up with the highest chances (30-50%) along and north of I-94 with
the instability axis dropping off into southeast MN. The 28.12z CAMs
tend to show mostly isolated showers with maybe the more aggressive
solutions trying to form a weak line of showers in central
Wisconsin. Regardless, really not expecting significant rainfall
totals, with totals on the order of a tenth or less.
TOMORROW:
With the passage of the weak frontal boundary overnight into the
morning, temperatures will trend cooler for the day tomorrow with
highs in the 70s for much of the region. Additionally, the 28.12
HRRR and RAP vertically-integrated smoke fields want to bring in
more Canadian wildfire smoke in behind the front, as has been
previously seen this summer. Generally not expecting much to be
surface based but skies could be hazy during the morning hours
tomorrow as a result.
LOOKING AHEAD:
An upper-level ridge builds in mid-week and beyond bringing another
round of hot weather to the Upper-Midwest. An early look at ensemble
guidance shows a consistent signal for high temperatures in the low
to mid-90s for much of the area this weekend. Dew points will be
lower than our last stretch so that could help keep heat indices at
or below 100. Regardless, the main message in the extended forecast
is the return of hot temperatures with little to no chance for
precipitation.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1045 PM CDT Mon Aug 28 2023
VFR conditions are expected through the TAF period outside of a
few pockets of lower visibility restrictions associated with some
showers north and east of LSE at the start of the period, which
should exit before sunrise. Winds veer to the NNW behind a front
tonight and increase to around 10G20kts during the afternoon, most
notably west of the Mississippi River. These winds lessen and veer
to the northeast/east after 00Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
DISCUSSION...KAA/Naylor
AVIATION...Skow
AREA FORECAST DISCUSSION
National Weather Service Bismarck ND
1004 PM CDT Mon Aug 28 2023
.UPDATE...
Issued at 1003 PM CDT Mon Aug 28 2023
For late evening update main change was to spread areas of smoke
though the remainder of western and central North Dakota through
Tuesday. Various observations throughout the area are showing
some reduction in visibility, so decided just to blanket the
mention of smoke. Remainder of forecast looks good.
UPDATE Issued at 657 PM CDT Mon Aug 28 2023
Going forecast remains in good shape. A few locations are noting a
little reduction in visibility over northern portions of the area,
but so far the lowest is around 6 miles. Will continue to watch to
see if any significant drops occur.
&&
.SHORT TERM...(This Evening through Tuesday)
Issued at 210 PM CDT Mon Aug 28 2023
Smoke highlights the short term forecast.
Weak high pressure was situated over western and central ND early
this afternoon. Other than some fair weather cumulus cloud north
central into the James River Valley, skies were clear over western
and central ND. However smoke continues to spread south from
Canada. Slight visibility restrictions can be seen from northeast
Montana into northwest and north central ND.
For tonight and Tuesday. the RAP smoke model continues to show
smoke aloft and at the surface spilling into the state from
Canada. Although the surface smoke may be a bit overdone, we are
starting to see some lowering visibilities. Therefore we have
introduced areas of smoke tonight through Tuesday evening. The
highest concentrations at the surface and aloft look to be late
tonight through Tuesday morning, with smoke clearing and/or
concentrations diminishing thereafter.
Other than the smoke, the short term period remains quiet with
dry conditions tonight and Tuesday with generally light winds.
Lows tonight will be mostly in the 50s and highs Tuesday in the
80s, except for some mid-upper 70s around the Turtle Mountains.
.LONG TERM...(Tuesday Night through Monday)
Issued at 210 PM CDT Mon Aug 28 2023
The long term period features an upper level low tracking north of
the forecast area Wednesday/Thursday with another system lifting
into the area late in the extended period.
The RAP HRRR show smoke thinning and/or moving out of the area
Tuesday night. If the smoke doesn`t clear out Tuesday night,
Wednesday should really knock it out as surface and upper level
both turn south to southwest respectively, ahead of the
approaching upper level low.
Fire weather concerns are possible Wednesday afternoon as the
surface low deepens and tracks from central into eastern Montana.
This would put over western ND Wednesday morning and propagating
eastward into central ND by Wednesday afternoon. Winds diminish in
the far west Wednesday afternoon and then shift westerly as the
surface trough pushes into the state. Lowest mid-late afternoon
humidities are expected to be in the far west, with strongest
winds at this time in the central portion of the state. Although
the strong winds and low humidities don`t really line up well for
critical fire weather conditions, there may be a period of time in
from mid-late afternoon where there is just enough of an overlay
to possibly produce some near critical fire weather conditions
from northwest ND, Southeast to around Grant and western Sioux
counties in the far southwest/south central.
Wednesday evening will bring the potential for showers and
thunderstorms as the upper low lifts into Saskatchewan and drags a
cold front through western and into central ND. There are some
steep lapse rates and a bit of moisture pooling ahead of the cold
front, with moderate to strong deep layer shear and forcing for
ascent with the approaching upper level low. Forecast soundings
over western ND compared to yesterday look to have a little more
capping potential with warm air aloft. This capping looks more
extensive as you get into central ND. Thus at this time the
potential for stronger storms looks to be limited to mainly
western ND. Certainly something we will continue to monitor.
On Thursday the upper low tracks across southern Saskatchewan into
southern Manitoba. The track does look to be a bit farther north
than yesterday. This would keep shower activity limited to mainly
the far north, and winds in the south wouldn`t be quite as strong,
which would limit any fire weather concerns. Friday through Sunday
we see a warming trend as upper level ridging builds over the
forecast area, ahead of another upper level trough that has it`s
sights set on the Northern Plains. Although uncertainty at this
timeframe is quite high, it may take a track a little farther
south which could bring better precipitation chances across a
larger portion of the forecast area. Stay tuned.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
Issued at 657 PM CDT Mon Aug 28 2023
Areas of smoke will continue over the area, with localized MVFR
conditions possible. Otherwise, VFR conditions will prevail.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...JJS
SHORT TERM...TWH
LONG TERM...TWH
AVIATION...JJS
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
606 PM CDT Mon Aug 28 2023
...New AVIATION...
.SHORT TERM...
(Tonight through Tuesday night)
Issued at 216 PM CDT Mon Aug 28 2023
Latest HRRR model run does not show much in the way of convection
over most of the short term period. Other model guidance has been
treading a bit downward on the chances of rain as well. As such,
PoPs have been reduced a bit for the short term period so that
showers and thunderstorms are isolated at best. Subsidence from the
developing Tropical Storm Idalia are a factor that the models are
going with in reducing rainfall potential. Models still have a weak
cold front towards the north trying to push south, but it seems that
it gets into the Northern Ranchlands around late tonight and early
tomorrow, before then starting to pull back a bit towards the north
and stalling out north of Deep South Texas and the Rio Grande
Valley.
Outside of the lowered possibility of rain, winds are going to be
light through the short term period, but will shift towards the
north by tomorrow, and then change again towards the southwest. Dry
air is expected for tomorrow which will help keep the area out of
Heat Advisory criteria and the air should feel less humid as well.
While the minimum relative humidity is low for the region, fire
weather concerns are limited due to the winds being so light. High
temperatures for tomorrow see 100s for most of the region, however
along the coast the highs will be in the upper 90s. Low temperatures
for tonight are expected to be in the upper 70s to low 80s, while
tomorrow night will be in a similar range, but with a greater spread
of temperatures in the upper 70s rather than lower 80s.
&&
.LONG TERM...
(Wednesday through next Monday)
Issued at 216 PM CDT Mon Aug 28 2023
As Idalia is working through the Florida peninsula on Wednesday
and broad low pressure expands across the northern Gulf of Mexico,
very dry air arrives into Deep South Texas by way of a weak
stalling boundary and deep northerly to northeasterly flow
rounding the mid-level ridge across the Four Corners. As the ridge
heads east through the Plains and into the Ohio River Valley over
the weekend, low pressure across the western Gulf becomes cut off
and persists offshore through the holiday weekend before working
inland on Labor Day. Moisture gradually increases over the weekend
into next week and tries to bring back rain chances, mainly along
the seabreeze Saturday through Monday. POPs remain rather low at
this time. Triple digit heat continues for most inland locations
with a slight reprieve possible along the coastal counties and
lower to mid valley over the weekend with any increased cloud
cover.
Potential coastal hazards locally from Idalia will need to be
monitored mid week. Long period swell Wednesday into Thursday will
build offshore seas and likely enhance rip currents along the
lower Texas coast. With the full moon on Wednesday, astronomical
tides will be a little stronger as well, so coastal run-up may
also be in play during high tides. Confidence is a little low at
this time, due to the limited run the cyclone has across Gulf
waters leading into landfall and unknown strength of the rapid
intensification expected over the next 24 to 36 hours.
Fire weather is also worth monitoring through the long term
period with RH values generally less than 30 percent across most
inland areas Wednesday and Thursday, and tanking into the teens
across Zapata County Wednesday through Friday. At this time, 20
foot winds either remain just below criteria or arrive as RH
values recover into the evening hours. Regardless, with crispy
fuels and the summer wildfire season in full swing, RH values this
low are concerning.
&&
.AVIATION...
(00Z TAFS)
Issued at 605 PM CDT Mon Aug 28 2023
VFR conditions will prevail through the TAF period at all
aerodromes. Winds will remain light and variable, especially in
the overnight hours.
&&
.MARINE...
Issued at 216 PM CDT Mon Aug 28 2023
Tonight through Tuesday Night..Favorable marine conditions
are expected tonight through Tuesday night with light and variable
winds and low waves. A weak cold front is expected to push into the
northern waters late tonight or early tomorrow before moving back
north. Isolated showers and thunderstorms are possible, most likely
occurring tomorrow.
Wednesday through Monday...Idalia may make landfall in Florida as
a major hurricane on Wednesday, potentially building a long
period swell across the Gulf into late Wednesday and Thursday.
Gulf seas may build to around 5 to 7 feet before more favorable
marine conditions generally return through the holiday weekend.
Persistent low pressure across the western Gulf of Mexico will
gradually build rain chances through Monday, generally offshore
overnight and onshore each morning. Winds and seas will be higher
near any thunderstorms.
&&
.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE 80 100 79 99 / 0 10 10 10
HARLINGEN 77 100 75 100 / 0 20 0 0
MCALLEN 80 103 78 103 / 0 10 0 0
RIO GRANDE CITY 80 102 77 104 / 0 10 0 0
SOUTH PADRE ISLAND 82 91 81 91 / 0 10 10 0
BAYVIEW/PORT ISABEL 78 97 77 96 / 0 10 0 0
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
SHORT TERM...64
LONG TERM....56
AVIATION...68
Area Forecast Discussion
National Weather Service Columbia SC
823 PM EDT Mon Aug 28 2023
.SYNOPSIS...
A surface boundary will remain near the forecast area through
Tuesday serving as the focus for showers and thunderstorms.
Rainfall may be moderate to heavy at times resulting in
localized flash flooding. Tropical Storm Idalia is then expected
to be pulled north towards the forecast area with possible
impacts Wednesday into early Thursday. Much drier and cooler
air moves in behind the system to close out the week.
&&
.NEAR TERM /THROUGH 7AM Tuesday/...
Showers and storms today more scattered in nature than
yesterday and although the front remains across the forecast
area, it is a bit more diffuse with weaker surface convergence.
RAP soundings are also indicating some weak capping across the
area, limiting storm coverage. Still the storms that are
developing are producing fairly efficient rain rates with MRMS
estimates between 1 to 2 inches per hour. Should continue to see
storms weaken into tonight with the higher chances for any
linger convection in the NW area as a shortwave moves into the
Upstate. Seasonal temperatures once again tonight with stratus
developing across the area, in the low to mid 70s.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Tuesday and Tuesday Night: The weather on Tuesday will be
similar to today as a remnant surface boundary remains draped
across the region. Isolated to scattered showers and
thunderstorms should redevelop during the afternoon and evening
hours. High PWATs and increasing moisture ahead of Tropical
Storm Idalia will continue to promote the risk of heavy rain
from any robust convection which is reflected in the Marginal
(1/4) risk on the Day 2 WPC ERO. Showers and thunderstorms are
most likely across our northern and western counties. Localized
flash flooding will again be possible, especially for locations
that have already seen heavy rainfall. Rain chances will
increase Tuesday night as Idalia approaches from the south.
Highs will be in the upper 80s to near 90 degrees with lows in
the lower 70s.
Wednesday and Wednesday Night: Not much change in the forecast
for Idalia with the latest NHC track taking the cyclone center
into the Big Bend area of Florida early Wednesday morning as a
major hurricane passing along the South Carolina coast as a
strong tropical storm late Wednesday into Wednesday night. It is
important to note that shifts in both track and intensity are
possible which could deviate the forecast slightly. Having said
that, the primary hazard remains heavy rainfall and the associated
flooding risk, especially given the antecedent conditions. The
Day 3 WPC ERO places much of the FA in Slight (2/4) risk for
heavy rainfall with the southeastern counties in a Moderate
(3/4) risk. Rainfall amounts of 4 to 6 inches, with locally
higher amounts, are possible for the eastern Midlands, with
lesser amounts farther inland. The clouds and rain keep
temperatures from moving much with forecast highs in the upper
70s to near 80 degrees falling into the mid to upper 70s by
daybreak Thursday.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
Much drier and cooler air moves in behind Idalia with dry
conditions expected through the extended. The rain and wind
should diminish quickly on Thursday as the cyclone pulls away
from our forecast area. A potential Cold Air Damming setup on
Thursday will result in temperatures well below normal. The
upper ridge centered over the Southwestern United States shifts
east and strengthens later this week into the weekend with
temperatures gradually rising through the period. It looks like
highs will remain below normal until early next week when the
ridge axis is expected to reach the Eastern CONUS.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
Restrictions expected again tonight at all TAF sites.
Multiple things are ongoing across the area that will lead to
another round of restrictions tonight. We have the weak boundary
that has been set up near the region for several days, along
with a sea breeze boundary pushing in from the southeast. This
will likely push through much of the area, brining a slight
uptick in surface moisture. Meanwhile, we have weak
southeasterly flow just above the surface, pushing some lower
moisture air in aloft. Given how moist we are, and the rain we
have received over the past several days, expecting fog/stratus
to develop later. It doesn`t look like a home run on either
side; models are generally split on whether it is a night
dominated by fog or by stratus. I tend to think we are more
likely to see stratus between 400 and 700 feet, with patchy IFR
fog. So I have that prevailing at all sites, generally from 08z
to 14z. There should be a low-level jet in place early in the
night, which should help keep it mostly stratus, but it wouldn`t
surprise me to see more dense fog develop if we do see that
low-level jet weaken. By tomorrow, winds will pick up out of the
south and southeast, with another round of showers and
thunderstorms possible. Added VCSH to account for this
possibility.
EXTENDED AVIATION OUTLOOK...Restrictions likely into mid- week
as moisture increases and possible impacts from Idalia Wednesday
into Thursday. Drier weather expected for Friday and into the
weekend.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
&&
$$
Area Forecast Discussion
National Weather Service Dodge City KS
607 PM CDT Mon Aug 28 2023
...Updated Aviation...
.SHORT TERM...(This evening through Tuesday night)
Issued at 115 PM CDT Mon Aug 28 2023
The far western counties are in general thunderstorm outlook for
late this afternoon and this evening. MUCAPEs to several hundred
J/kg in the general area of a subtle surface trough shifting into
the area late evening can be the focus area for sustained showers
or storms moving in from Colorado. The high res ensemble forecast
CAMs members stamps were not very convincing... or of very high
confidence of any activity for our area earlier this morning, but
as of the latest 12z runs the HRRR and ARW are more aggressive
with bringing in a cluster of storms to the far western counties,
including Scott City area (22-00 UTC in the case of the HRRR) to
Elkhart and the far southwest a little later in the evening.
Overnight won’t be quite as cool as the mid 50s were last night.
A fairly uniform low 60s minimum temperature grid is forecast for
Tuesday morning under mostly clear sky (northern sections) and
light northerly wind behind the exiting surface trough.
.LONG TERM...(Wednesday through Monday)
Issued at 115 PM CDT Mon Aug 28 2023
Wednesday will be about the last reasonably near normal day
before the temperatures start ramping up through the 90s for the
rest of the typical workweek. As far as daily records go... the daily
record highs could be at risk of falling Saturday. (DDC is in the
103-107 F range for the 1st-3rd of Sept with respect to records).
Friday the record is 107 and probably too high to be at risk,
however Saturday might be a day where the record can get tied or
exceeded at 103F.
There appears to be a bit more agreement in the last couple of
EPS vs GEFS ensemble runs with respect to the temperatures for the
weekend and beyond. These ensemble means are mirroring one
another more closely both on temperatures and trends, with upper
90s to around 100 degrees – the hottest period being in the “this
weekend” though about mid week, and little relief following. The
pattern remains intact with westerly flow well to the north in
Canada and a large thermal ridge keeping the weather hot through
week 2, basically through the second week of September.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 602 PM CDT Mon Aug 28 2023
In general the flight category will be VFR for all terminals
during the time period. Isolated to widely scattered storms are
possible between now and 04Z that could lead to some VCTS
conditions for HYS, GCK, and DDC. However given the scope and
isolated nature of the storms...left out the VCTS wording and will
amend accordingly if a rogue storm comes within the airports.
Winds will pick up after 15Z and be breezy between 10-20 kts for
all terminals through 00Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 63 89 60 91 / 10 10 0 0
GCK 60 87 56 88 / 20 0 0 0
EHA 62 86 57 89 / 30 10 0 0
LBL 61 88 57 90 / 30 10 0 0
HYS 62 89 59 91 / 20 0 0 0
P28 65 91 63 91 / 10 10 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Tatro
Area Forecast Discussion
National Weather Service Duluth MN
840 PM CDT Mon Aug 28 2023
.DISCUSSION...(This evening through Sunday)
Issued at 307 PM CDT Mon Aug 28 2023
Key Messages:
1. Scattered showers and storms the rest of this afternoon through
tonight. A few stronger storms capable of producing small hail and
gusty winds may be possible into this evening.
2. Mainly dry weather is expected this week, with the exception of a
chance (20-40%) of showers/storms Thursday evening into Friday
morning.
3. Turning hot again late this week into the weekend.
Today - Tonight:
Widely scattered showers and thunderstorms have begun developing
from the Brainerd Lakes Lakes up into the Boundary Waters Canoe
Area Wilderness in the vicinity of a southeastward advancing cold
front this afternoon. Warm advection ahead of the front has
brought in 300-800 J/kg of MLCAPE, with 30-40 knots of effective
bulk shear along and ahead of the cold front. Some higher-level
clouds and poorer mid-level lapse rates (<6C/km) should keep
storms sub-severe this afternoon and evening. Low-level lapse
rates of 7.5-8.5C/km are a bit better, however. Taking all of
these factors into consideration, a few strong storms are possible
and could be capable of small hail and sub-severe gusty winds.
The best thunderstorm coverage as we get into the later part of
the afternoon and evening remains across the Minnesota Arrowhead
into NW Wisconsin where the left exit region of the upper-level
jet will support the most synoptic-scale lift. This round of
storms should exit southeast of our NW Wisconsin counties later
this evening as the cold front moves out of our area.
Given the scattered nature of the storms today, many areas will see
little to no rain. HREF guidance does paint the potential for
anywhere that does see thunderstorms move overhead to pick up a
quick 0.25-0.75", with the highest of these amounts in the
Minnesota Arrowhead and NW Wisconsin, but these higher rainfall
amounts will be on a localized basis.
Some post-frontal light showers should linger tonight into Tuesday
morning, primarily over northern and northeastern Minnesota, as the
main axis of the upper-level trough dives southeast across the
Northland. Additional rainfall tonight into Thursday morning should
be light, on the order of a tenth of an inch or less.
Some areas of fog will be possible again tonight in locations that
can see some partial clearing tonight, given light winds and
lingering low-level moisture. Best fog potential would be in the
Iron Range and across portions of NW Wisconsin, as well as any
locations that receive rainfall.
Tuesday:
NW flow aloft and at the surface will advect slightly cooler
weather into the Northland for Tuesday. The HRRR and RAP smoke
models also point to some smoke (mainly aloft) moving over the
region, which should result in some milky skies. Have increased
the sky cover forecast to account for this. Onshore flow off of
Lake Superior should keep temperatures slightly cooler, ranging
from the mid-60s in nearshore areas to the mid-70s over the
Brainerd Lakes into the St. Croix River Valley.
The coldest temperatures of the week are expected Tuesday night as
skies clear out, with some upper-30s to potentially mid-30s in
spots across north-central Wisconsin for lows. Will need to
continue to monitor forecast trends closely for some limited frost
potential Tuesday night into early Wednesday morning.
Wednesday - Thursday:
An upper-level ridge will build into the Upper Midwest for the
middle of this week, leading to dry weather for Wednesday and most
of Thursday. We will also see the start of a gradual warming trend
with highs in the 70s on Wednesday and mid-70s to low-80s on
Thursday. Winds turn very breezy out of the south beginning on
Thursday as the surface pressure gradient increases ahead of an
approaching upper-level trough and associated surface front late
Thursday into Friday.
Thursday PM - Friday:
Another chance for some showers and storms return to the
Northland sometime Thursday afternoon/evening into Friday morning as
another upper-low opens up into a trough as it cuts eastward
across far southern Manitoba into NW Ontario. Precipitation
chances remain around 20-40% with this system given the better
synoptic lift is currently forecast to remain north of the
international border. Otherwise, winds remain gusty into Friday,
with temperatures climbing into the low- to mid-80s for most of
the Northland.
Labor Day Weekend:
A stronger axis of the upper-level ridge moves into the central
U.S. this weekend into the very early portion of next week,
bringing a return of hot, summer-like conditions with it. High
temperatures should climb well into the 80s from Saturday-Monday,
while some low-90s cannot be ruled out on Sunday and Monday across
our central MN into southern tier of NW Wisconsin counties.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 839 PM CDT Mon Aug 28 2023
Update: Introduced some vicinity showers entering from the north
early tomorrow morning for northern MN.
Scattered showers and storms are moving southeast across the
Northland this evening. This activity will quickly end over the next
few hours leaving the region with VFR conditions by late evening.
There is potential for fog to develop tonight. The better chances
will be across HIB and INL. Any fog that does develop will erode
after sunrise leaving the region in VFR conditions once again.
&&
.MARINE...
Issued at 322 PM CDT Mon Aug 28 2023
Predominately southwest winds around 5 to 10 kt the remainder of
this afternoon will shift to northwesterly this evening and
northerly tonight behind a cold front. Some scattered showers and
storms remain possible over the Lake from this afternoon into
evening before moving southeast of the area tonight. Could see
some lingering light showers over western Lake Superior tonight
into early Tuesday morning, but chances are only around 20 percent
or less.
Winds turn east to northeast for Tuesday, which could lead to some
localized gusty winds up to 15 to 20 kt during the daytime on
Tuesday, particularly for the outer Apostle Islands into Saxon
Harbor. This could result in wind-driven waves up to around 3 ft
as well for those locations. Winds and waves weaken Tuesday night,
with winds then shifting to southerly by Wednesday as surface high
pressure moves to our east.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 55 69 49 75 / 30 20 0 0
INL 51 69 46 76 / 20 10 0 0
BRD 54 78 52 78 / 0 10 0 0
HYR 55 70 44 75 / 30 10 0 0
ASX 57 65 44 76 / 40 20 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&
$$
DISCUSSION...Rothstein
AVIATION...Britt
MARINE...Rothstein
Area Forecast Discussion
National Weather Service Grand Forks ND
1038 PM CDT Mon Aug 28 2023
.UPDATE...
Issued at 956 PM CDT Mon Aug 28 2023
Temperatures remain on track this evening with most locations now
in the upper 60s to lower 70s. Look for light and variable winds
overnight, with the potential for smoke and haze working down
toward the surface in some areas.
UPDATE Issued at 637 PM CDT Mon Aug 28 2023
Winds are diminishing this evening with overall quiet weather
being observed. A few sites are reporting haze and smoke,
primarily within the norther Red River Valley. Temperatures are in
the middle 70s to low 80s at this time, with the forecast
remaining on track.
&&
.SHORT TERM...(This evening through Tuesday night)
Issued at 235 PM CDT Mon Aug 28 2023
-A few showers possible in Lake of Woods area late tonight.
-Smoke aloft today, could possibly get down to the surface
tomorrow.
Northwest flow continues across the region, with a weak embedded
shortwave digging down from Canada into MN tonight. While the best
forcing will be to our northeast, many of the CAMs have some
shower activity into the Lake of the Woods region late tonight
into tomorrow morning. There is some less than 500 J/kg of MU CAPE
possible, so some lightning is not out of the question but think
severe is unlikely. The shortwave digging down should help push a
weak backdoor cold front into the region tomorrow, with winds
again picking up from the north and temps staying in the upper 70s
to low 80s.
There has been a fair amount of smoke aloft for much of the day
today, although satellite loop shows some thinning in our northern
counties. There is the possibility of the weak front helping bring
some smoke down to the surface late tonight into tomorrow. The
HRRR and RAP both have some decent concentrations of near surface
smoke in their model runs. Thus, included a mention of patchy
smoke in the grids tonight into tomorrow.
.LONG TERM...(Wednesday through Monday)
Issued at 235 PM CDT Mon Aug 28 2023
Wednesday and Thursday...Upper ridging moves east, with a fairly
strong upper low moving into the Northern Rockies. That system will
lift northeastward into Saskatchewan for Thursday, with much of the
upper support to our north. However, it does look like there will be
a surface trough and some warm air advection coming out into the Red
River Valley. The strong system moving through Canada should crank
up winds late Wednesday into Thursday, although not quite up to 30
kts that the NBM gives us so toned that down a bit. The breezy
southerly winds should be enough help dew points recover back into
the upper 50s to low 60s after the cool frontal passage early in the
week. NBM probabilities around only around 44 percent for CAPE
values above 1000 J/kg Thursday, which isn`t terribly impressive.
However, with forcing and at least some instability, this time
period will be the best shot for convection.
Friday through Sunday...The upper low in Canada pulls off to the
east with ridging building back over the midwest. R climate
percentiles and ECMWF extreme forecast index show a pretty good
signal for heat for the first part of the holiday weekend, although
the epicenter will be to our south. The probabilities for getting
above 90 degrees are around 40 percent for Saturday and up around 60
percent for Sunday. Trends have been a bit on the high side with the
blend this summer, so did tone it down a few degrees but should
still be well above seasonal highs for this weekend.
Monday...Southwesterly flow aloft sets up as the upper system
departs, and should be a bit more active with many ensemble members
bringing a shortwave out into the Plains. Above average temps and
some 20 percent probabilities for precip seem reasonable with this
general pattern, with details not yet resolvable.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1029 PM CDT Mon Aug 28 2023
VFR conditions prevail through the period at all sites. Light and
variable winds are expected through the overnight hours before
increasing out of the northwest, then north through Tuesday
morning. As winds shift northward, smoke is expected to work back
into the area, with minimal mixing to the surface. Some guidance
is bringing a stratus deck into the area around 14Z, mainly north
of KGFK and KDVL. Confidence is somewhat low regarding potential
impacts on ceilings, but if this develops, MVFR conditions would
be possible starting around mid morning.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
UPDATE...Lynch
SHORT TERM...JR
LONG TERM...JR
AVIATION...Lynch
AREA FORECAST DISCUSSION
National Weather Service Sioux Falls SD
1010 PM CDT Mon Aug 28 2023
.SHORT TERM...(This Evening through Tuesday Night)
Issued at 248 PM CDT Mon Aug 28 2023
KEY MESSAGES...
1. Wildfire smoke will filter in on Tuesday through at least early
Wednesday, causing periods of poor air quality and reduced
visibility.
2. Gusty south winds Thursday.
3. Warmer than normal weather continues through the weekend and well
into next week with no appreciable rain.
TONIGHT: A pleasant evening is in store for the region. Drier air
and a light north wind spread in behind the passing weak cold front,
aligned from Lake Superior southwestward to the Iowa Great Lakes and
Sioux City metro area by early evening. Aloft, we come under NNW
flow aloft (instead of NW) as an upper trough axis slides through
the Northern Plains. Already evident upstream on satellite, wildfire
smoke from the Northwest Territories will stream in aloft late
tonight through Tuesday. Temperatures will drop pretty quickly after
dark, but thick smoke aloft may temper nocturnal radiative cooling
some.
TUESDAY: The main impact will be air quality and visibility issues
related to near surface wildfire smoke. Both the HRRR and RAP models
continue to stream wildfire smoke in aloft and mixing down to the
surface around mid day. Upstream observations in Manitoba and
Saskatchewan range with visibility from 3 to 8 miles. Expect that to
translate downstream so added areas of smoke in through Tuesday
night, after which confidence decreases as detailed in the Long Term
section. Though this period of smoke does not look to be as
prolonged or extreme as those we`ve seen earlier this year,
sensitive groups may consider limiting outdoor or strenuous physical
activities Tuesday afternoon and night.
Expect a filtered appearance to sunshine tomorrow thanks to thicker
smoke aloft. Will see a slightly cooler day with highs in the upper
70s to mid 80s, low humidity, and a north breeze.
.LONG TERM...(Wednesday through Monday)
Issued at 248 PM CDT Mon Aug 28 2023
WEDNESDAY: The weather pattern starts to shift as strong sfc high
pressure builds east and upper level ridging builds through. It`s
tough to say how long near surface smoke will linger in the region
on Wednesday, but southerly return flow and a shift to westerly flow
aloft means we should see some improvement to air quality and
visibility. Smoke and increasing south winds will be the main
impacts on an otherwise slightly warmer, dry, unremarkable day.
THURSDAY: South winds crank up as the Central Plains lies between a
stacked upper low over Saskatchewan and stalled high pressure over
the Great Lakes. Given the propensity for overdone NBM winds,
decreased winds slightly, but still expect a breezy day. Model
soundings suggest it is unlikely that we will tap into the strongest
winds (40-50 kts at 875-800mb) but we can easily expect gusts to
peak in the 30s, perhaps even occasionally into the 40s. Strong mid
level warm air advection will help eek temperatures a few degrees
warmer as well, yielding highs ranging from the 80s (east of I-29)
to 90s (west of I-29).
FRIDAY THROUGH NEXT WEEKEND: Main impact continues to be warmer than
normal temperatures, rising through the weekend as upper ridging
stalls over the Central and Southern Plains in response to departing
Hurricane Idalia. Blended in a bias-corrected consensus of model
guidance to decrease high temperatures a few degrees for Friday
through Monday in response to influence of outlier GEFS/GFS heat.
Mostly dry conditions with highs in the 80s and 90s will remain
common through at least early next week as temperatures aloft remain
in the top 3% of EPS guidance for this time of year.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1008 PM CDT Mon Aug 28 2023
VFR through the period. There is a chance for MVFR visibility in
smoke during the day on Tuesday, but confidence is low right now.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.
&&
$$
SHORT TERM...BP
LONG TERM...BP
AVIATION...08
Area Forecast Discussion
National Weather Service Glasgow MT
130 PM MDT Mon Aug 28 2023
.DISCUSSION...
Afternoon Update:
Not too much was changed with this package. Smoke and haze that
shrouds the area should lift out Wednesday as the upper/mid level
low moves in. Also increased chances of Thunder Wednesday
afternoon as the upper low comes very close to the CWA and models
probably underdoing this element.
Also, with windy conditions expected with this system, I hoisted
the Lake Wind Advisory flag from tomorrow (Tuesday) evening till
Thursday evening. TFJ
MORNING DISCUSSION:
Synoptic Setup: Forecast begins with hot high pressure situated
over the Desert Southwest and a ridge juts north through the
Intermountain West, the Pacific Northwest, southern British
Columbia, and comes to crest over northern Alberta. To the
northeast an equally large opposing trough lies over the Hudson
Bay. Northeast Montana lies between these two features with the
ridge having more influence at this time. Farther west a large
closed low resides of the coast of the Pacific Northwest and is
pressing inland.
Today through Tuesday morning: While the dry ridge will have the
main influence during this time, the RAP smoke model is pointing
toward progressively deteriorating conditions from smoke for
health and visibility to come rolling down the high plains of
Alberta and Saskatchewan into northeast Montana. While confidence
in timing around Noon for entry seems high, there is a confidence
problem with intensity as smoke may be stronger or less so than
predicted by the RAP. This smoke will stay on and get worse
through the night. Some clearing may be possible by Tuesday as
southeast winds develop along a lee side mountain trough and begin
mixing. Meanwhile, the closed low to the west will move on shore
and press east rapidly during this time.
Tuesday afternoon into Wednesday: Strong winds on Tuesday are
expected to intensify into the evening hours. With the eastward
progression of the low the gradient below the lee surface trough
is expected to strengthen. Winds from the southeast will become
gusty near sundown, but RH should begin creeping up during this
time keeping the overlap of conditions for Fire Weather from just
barely reaching criteria. In addition a layer of limited moisture
is expected with the frontal passage Wednesday and this should
also help to partially reduce fire weather concerns as well.
Wednesday night into Thursday: Strong west winds behind the front
are possible along with lingering showers across the northern
zones as the low exits to the east.
Thursday night onward: Ridge to the south will build back into
the region briefly and then be scooped away by Sunday. There is
some uncertainty in the order of operations through Monday before
things come back into sync with the ensembles among each other.
These time periods of the forecast will be subject to rapid
change with future updates. GAH
&&
.AVIATION...
UPDATED: 1930Z
FLIGHT CONDITIONS: MVFR/Possible Brief IFR at KGGW and KOLF
DISCUSSION: Wildfire smoke from western Canada has moved in and
will bring MVFR vsby and brief IFR conditions can be expected,
mainly from 11-14z Tuesday at KGGW and KOLF.
Pilots should watch for Slantwise visibility reductions through
Tuesday Night.
Smoke/haze will linger into Tuesday Night but should lift out
Wednesday.
WIND: North to northwest at 5 to 15 kts becoming light and
variable in the evening through tonight. Then late Tuesday begin
to increase from the SE.
TFJ
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...
Lake Wind Advisory from 8 PM Tuesday to 9 PM MDT Thursday For
Fort Peck Lake for Central and Southeast Phillips...Central and
Southern Valley...Garfield...McCone...Petroleum.
&&
$$
weather.gov/glasgow
Area Forecast Discussion
National Weather Service Lubbock TX
632 PM CDT Mon Aug 28 2023
...New AVIATION...
.SHORT TERM...
(This evening through Tuesday)
Issued at 255 PM CDT Mon Aug 28 2023
Current 500 mb water vapor and RAP analysis shows a high pressure
system sitting over Southern California. The high will remain
stagnant through tomorrow as it becomes elongated over the eastern
Pacific and Southern California. Winds will remain light, ranging
from 5 to 15 mph and varying between north and east through
tomorrow evening. Lingering clouds still persist from this
mornings rain showers limiting diurnal heating but northerly flow
aloft will continue to push the cloud cover out of the area. A
lull in the activity this afternoon as a swath of upper-level dry
air moves in from the north. Current visible satellite shows
shallow cumulus developing along the Texas/New Mexico border but
due to an over worked environment and little instability storms
are not expected. However, monsoonal moisture along the Rockies
has initiated showers and storms this afternoon across
northeastern New Mexico. This activity will be the focal point for
rain chances this evening and late tonight. Storms are expected
to remain below severe limits with gusty winds as the main threat.
The best chance for showers and storms will be generally west of
highway 385. Near normal temperatures tonight in the 60s across
the forecast area. Another lull in precip tomorrow morning before
a potential round of isolated showers and storms returns to
portions of the High Plains tomorrow afternoon. If storms develop
tomorrow, the high temperature forecast may be tricky. High
temperatures tomorrow are currently forecast to range from the mid
to upper 80s mainly along the Caprock and lower 90s off the
Caprock.
&&
.LONG TERM...
(Tuesday night through next Sunday)
Issued at 255 PM CDT Mon Aug 28 2023
The 12Z upper air map currently shows the 595 dam upper level high
over the desert southwest and is expected to track back to the east
through the week. As the high begins to build back over our area, an
upper level trough will position itself over the ArkLaTx region. In
the Gulf of Mexico Tropical Storm Idalia will track north early this
week, and is expected to move onshore the coast of Florida Wednesday
morning. By Friday, a mid-level low in the Gulf of Mexico will move
onshore to the TX coast Friday moving inland.
Tomorrow night, some CAMs have isolated thunderstorms in the
southern South Plains tracking southward. However, precipitation
chances look to be minimal as storms begin to weaken with the loss
of daytime heating, therefore have kept PoPs below mentionable at
this time. After a nice few days of cooler weather, the hot
temperatures will make their return into west TX. Wednesday
highs will be warmer than previous days with height increases as
the upper level ridge tracks east over the Four Corners region.
With 850 mb temperatures ranging from 24-27C expect highs in the
90s across the area. A similar synoptic pattern will continue
Thursday onward with the GFS and ECMWF ensembles in agreement with
the progression of the upper level high moving to the east and
becoming centered over OK/KS by the end of the period. Thus, we
can expect temperatures to continue to slowly increase through the
remainder of the period. Precipitation chances through the
extended look to remain dry after Tuesday night, however, we will
continue to monitor a low in the Gulf of Mexico as it slowly
inches closer to the south TX coast Friday.
&&
.AVIATION...
(00Z TAFS)
Issued at 630 PM CDT Mon Aug 28 2023
Isolated to scattered northwest flow thunderstorms in northeastern
New Mexico likely to stay to the west of the terminals. A weakly
capped air mass Tuesday afternoon could end up allowing the
development of isolated showers/thunder, however confidence is
very low at this time. Will continue with simple VFR conditions
and light winds in the TAFs this cycle.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...10
LONG TERM....12
AVIATION...07
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1058 PM CDT Mon Aug 28 2023
.UPDATE...
Issued at 1057 PM CDT Mon Aug 28 2023
Updated to include 06z aviation discussion below.
&&
.DISCUSSION...(This evening through Monday)
Issued at 322 PM CDT Mon Aug 28 2023
KEY MESSAGES:
- Isolated, non-severe showers and thunderstorms east of I-35 this
afternoon and evening. Minimal chances for rain through Labor Day
after today.
- Confidence is increasing in another heat wave setting in over Labor
Day weekend.
Surface analysis at 230pm shows a somewhat diffuse cold front
extending from roughly Marshall, to St. Cloud, and Hibbing. Day
cloud phase RGB and radar mosaics show some attempts at getting
thunderstorms going up around Brainerd. Meso analysis shows about
500 j/kg of mlCAPE being present, but we are dealing with some
capping issues in the h7 to h6 layer that will make much more of a
southern extent than what we see now difficult. Given the meager mid
level lapse rates, CAPE, and shear, no severe weather is
expected.
Behind this front, we`ll have northwest flow through Wednesday,
which will keep temperatures mild and near normal. The only real
question both days will be the extent of Canadian wildfire smoke
we`ll have to deal with. For the most part, this looks to be
elevated, though the HRRR does show some potential for surface based
smoke to work into western MN, which is about the only thing we`ll
have to look out for Tue/Wed.
For Thursday through Labor Day and beyond, the main story will be
the potential for a significant September heat wave that would get
cranking Labor Day weekend. The culprit will be a large scale
pattern featuring a trough building down the west coast and an
anomalously strong h5 ridge building across the central CONUS into
the Great Lakes. EPS mean h85 temps increase into 10-15C above
normal range Sunday/Monday, so we`ll have the potential to see
record highs (upper 90s) for Sunday and Labor Day. When it comes to
precip chances, the atmosphere that builds in this weekend looks
hot, dry, and capped, so no rain is not expected. In fact, our rain
chances look pretty minimal over the next 2 weeks. These dry
conditions with hot temperatures means our drought is about ready to
start jumping into a higher gear.
As for changes from the NBM, we collaborated changes in two areas.
One was to switch over to using the experimental NBM for winds
Wednesday afternoon through Thursday evening to back off some from
what the NBM had (it looks breezy on Thursday, but not 40-45 mph
wind gusts breezy in western MN). In addition, given the influence
of the unrealistically hot GFS/GEFS on high temperatures in the
extended, we did mix in a little of the bias corrected CONSALL
values to knock about 2-4 degrees off of NBM highs for Friday
through Labor Day. In our last heat event, the NBM in the extended
consistently ran a bias of 3-5 degrees too high beyond Day 3 in the
forecast, with the primary culprit of that warm bias being the
unrealistically hot GFS within the blend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1057 PM CDT Mon Aug 28 2023
VFR conditions expected across all terminals this duration. High
smoke to move into western MN during the day tomorrow, possibly
dropping close to the surface and produce a VFR-worthy visibility
reduction due to HZ. Winds to remain generally northwest in the 5-10
kt range.
KMSP...No additional concerns.
/OUTLOOK FOR KMSP/
Wed...VFR. Wind SE 5-10 kts.
Thu...VFR. Wind S 15G25 kts.
Fri...VFR. Wind SW 15G25 kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&
$$
UPDATE...JPC
DISCUSSION...MPG
AVIATION...JPC
...Updated Aviation Forecast Discussion...
.DISCUSSION...
Issued at 332 PM CDT Mon Aug 28 2023
Key Messages:
- Near-surface smoke forecast to impact the region Tuesday into
Wednesday.
- Hot temperatures return to the region by Thursday and persist
well into next week.
-No precipitation is expected through the forecast
Tonight and Tuesday:
A weak mid-level shortwave continues to move through northwesterly
flow aloft. A few showers continue to show up on radar but not much,
if any, precipitation is making it to the ground in our area due to
such dry low levels. An increase in mid and high clouds is about the
best we will be able to do. A weak surface cold front will slowly
drift south across the forecast area overnight producing no
sensible weather besides a gradual wind shift to the northwest.
Smoke from Canadian wildfires is expected to drift down the above
mentioned ridge and overspread much of the area Tuesday into
Wednesday. The RAP and HRRR smoke model runs do indicate that the
smoke will be near-surface and so the Nebraska Department of Health
and Human Services has issued an air quality alert for moderate to
unhealthy air quality for eastern Nebraska Tuesday into Wednesday.
Wednesday through Monday:
Upper-level ridging will build into the central Plains while low-
level return flow increases. This will allow temperatures to heat up
across the Plains with the 850 mb thermal ridge near or over the
forecast area throughout the period.
Highs by Thursday should range in the low 80s across Iowa but into
the low to mid 90s across our western counties where stronger mixing
occurs. Temperatures gradually warm through the weekend with Sunday
looking to be the warmest day of the holiday weekend. Dewpoints
do not look to be as oppressive as this past heat wave due to such
dry conditions as of late, however they should still run in the
60s to possibly low 70s. For now, we are forecasting max heat
indices just below advisory criteria of 105 so will keep a close
eye on how it all unfolds over the next several days.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 619 PM CDT Mon Aug 28 2023
VFR conditions are expected at all TAF sites with winds becoming
increasingly northerly as a weak cold front sags south across the
area throughout the forecast period. Near-surface smoke is
expected to move into northeast Nebraska (KOFK, KOMA) from 1800
UTC through the end of the forecast period. Visibilities will be
slightly reduced during this time, however they are expected to
remain above 6 statute miles.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.
&&
$$
DISCUSSION...Kern
AVIATION...Darrah
Area Forecast Discussion
National Weather Service Pueblo CO
309 PM MDT Mon Aug 28 2023
.SHORT TERM...(This evening through Tuesday)
Issued at 242 PM MDT Mon Aug 28 2023
Key messages:
1) Scattered showers and thunderstorms will continue to be possible
this evening, especially over the eastern mountains and plains.
2) There is a low end chance of a storm becoming severe, if this
does happen, hail of up to 1 inch and outflow winds of 60 mph
will be possible.
3) Flash flooding will also be possible this evening, especially for
the burn scar and urbanized areas along the I-25 corridor and
Highway 50.
4) Tomorrow will be drier for most locations, with only a few
thunderstorms, mainly over the higher terrain.
Detailed discussion:
Tonight...
Lastest radar imagery shows that most of the convective development
is over the Rampart Range and southern Sangre de Cristos, which does
align best with what the HRRR is showing in the lastest model run.
Although all of the CAMs are generally similar in displaying the
majority of QPF located over the eastern mountains in general.
This will continue to move off over into the adjacent plains and
I-25 corridor by later in the evening, very similar to how storms
progressed yesterday. The main difference today is that there is
more instability shifted a bit further eastward to the Kansas
border and therefore storms will likely maintain their strength
and move off into the far eastern plains. CAMs have also been
hinting at the possible formation of an MCS by later this evening
that will be over the El Paso and Pueblo counties at around 8 PM
and then move southeastward over the lower Arkansas River Valley
and eventually over Prowers and Baca counties just before
midnight. This makes sense considering that this is where the
environment will be conditionally more unstable just before
convective initiation over this part of the CWA with nearly 2000
J/kg of MUCAPE over the Palmer Divide. Effective bulk shear is not
overly impressive, although there could be a few stronger storms
embedded in the cluster of storms as it merges and moves
southeastward that may produce severe strength outflow winds to 60
mph and possibly hail up to an inch. Otherwise, these storms will
likely just produce some heavy rainfall and therefore there is a
slight risk of flash flooding for some of the urbanized areas.
There will also be a risk of some flash flooding over the higher
terrain, especially for the burn scar areas if some of the storms
become tied to the terrain and remain nearly stationary over the
area. Otherwise, storms should continue to move towards the
southeast and I have lesser confidence of widespread storms further
south towards the New Mexico border, although there could be a
higher concentration of showers and storms over the southern Sangres
and Raton Mesa area. Model guidance does suggest that there could be
storms continuing into the overnight areas over portions of the
eastern mountains and plains, and even a few isolated showers and
perhaps a storm over the Pikes Peak region during the early morning
hours tomorrow. However I have less confidence of this, given that
the environment will be much more stable around that time.
Mostly cloudy skies over the higher terrain will begin to clear
going into the early morning hours tomorrow and it also become
mostly clear over the plains by around sunrise. Lows tonight will
drop down into the mid 60s to low 70s for most of the plains. For
high country, lows will generally be in the 40s to low 50s.
Tomorrow...
There will be considerably less moisture behind the exiting wave
with only some recycled moisture in the mid-levels for tomorrow. In
addition it will be relatively more stable in comparison to
conditions today, along with increasing subsidence as ridging begins
to build back in over the region. Because of this, afternoon and
evening thunderstorm activity will be suppressed and mainly confined
to the higher terrain, with the Rampart Range/Pikes Peak area having
the highest probability of a few thunderstorms developing by later
in the afternoon. Given the northwesterly flow aloft, some of these
storms may push off the mountains and over the northern I-25
corridor. There is less confidence of a few storms moving over the
mid to southern portion of the I-25 corridor (from the city of
Pueblo and southward) although it cannot be ruled out. For all
locations just east of the I-25 corridor, there will only be a
slight chance of a storm and it should remain dry for most areas
over the far eastern plains. Temperatures tomorrow will still be
slightly below the seasonal average tomorrow and fairly close to
what they were today. Highs will be in the mid to upper 80s for a
majority of the plains, and mid 70s to around 80 for the high
mountain valleys, with 50s and 60s for the higher terrain.
-Stewey
.LONG TERM...(Tuesday night through Monday)
Issued at 242 PM MDT Mon Aug 28 2023
Key Messages:
1) Hotter and drier Wed/Thu, with just some weak mountains
convection.
2) Continued hot for the holiday weekend, with increasing storm
chances from Friday onward, mainly along the Continental Divide.
Upper level high pressure will be centered over the srn Rockies
Wed/Thu before shifting into the central plains from Fri into the
weekend. Overall, pattern for Wed/Thu will be hotter and drier for
the region, though srn edge of upper wave moving through the nrn
Rockies may provide just enough forcing for some weak afternoon
storms on Wed, mainly across the higher terrain. Expect max temps
to warm about 10 degf Wed, then add another couple degrees on Thu
as high center will be nearby over nrn NM.
As high shifts east Fri into the weekend, renewed push of monsoon
moisture surges northward out of the desert southwest, leading to
increasing convection over the Great Basin and wrn Colorado Fri-
Sun. Greatest chance for storms for srn CO will be along the
Continental Divide through the period, with lesser storm
coverage/strength over interior valleys and the eastern mountains
where moisture will be more limited. Plains and I-25 corridor look
mainly dry through the period, with just some weakening spill-
over convection west of the Interstate. Max temps will remain hot
through the weekend, with readings near 100f over the lower
Arkansas Valley. Western U.S. upper trough lifts into the nrn
Rockies early next week, which will likely usher in a drier air
mass across the region starting on Mon, though enough moisture may
linger over the central mountains to pop a few afternoon storms
for one more day. On the plains, continued dry Mon with maybe some
slight cooling if cold front can arrive in time.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 242 PM MDT Mon Aug 28 2023
VFR conditions are expected to prevail for all TAF sites (KALS,
KCOS, and KPUB) throughout the forecast period. SHRA and TSRA are
expected to be in and around the vicinity of all stations, with the
best chance of occurrence at KCOS and KPUB, through the evening. If
SHRA/TSRA does develop, it could temporarily reduce CIGs and VIS to
MVFR/IFR criteria. It could also result in periodic windshifts and
increased wind speeds at both terminals. Winds will initially be
more synoptically influenced through the first 12 hours with winds
primarily out of the NE with gusts occasionally greater than 20 kts
at both KCOS and KPUB but then become more diurnally influenced for
the second half of the forecast period. Winds will be mainly
diurnally influenced at KALS and on the lighter side (less than 10
kts).
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...STEWARD
LONG TERM...PETERSEN
AVIATION...STEWARD