Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/27/23
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
806 PM CDT Sat Aug 26 2023
.UPDATE...
Issued at 805 PM CDT Sat Aug 26 2023
No major updates planned this evening since the forecast is doing
just fine.
&&
.SHORT TERM...(This Evening through Sunday Night)
Issued at 323 PM CDT Sat Aug 26 2023
Clouds continue to hold in pretty strong over the eastern CWA, but
the breaks are slowly increasing, and should continue to do so
through sunset. Latest RAP soundings suggest enough drying to
hopefully get meaningful cloud erosion between 22-00Z. Despite the
cloud cover, temps are still managing to get rather close to
original forecast highs.
For the overnight hours, the surface ridge axis begins shifting east
with south/southeast flow beginning to develop. Warm air advection
also kicks in and persists into Sunday out ahead of an approaching
warm front. Warmest temps aloft look to be over the western CWA,
where highs should be able to reach the upper 80s to low 90s. Rather
small probabilities for fog/low clouds tonight over the eastern CWA
where winds will remain the lightest. Something to look into and
monitor during the evening hours, but confidence too low at this
point to include fog in the forecast. Sky grids were increased
slightly out east towards Sunday morning to include possibility for
some lower clouds.
.LONG TERM...(Monday through Saturday)
Issued at 323 PM CDT Sat Aug 26 2023
Overall dry and mostly sunny conditons for the long term with
temperatures warming by midweek. EC/GFS/Canadian ensembles are all
in agreement with a highly amplified ridge over the western CONUS
and a troughing pattern over the eastern CONUS starting early next
week. This leaves the Northern Plains in northwest flow aloft. At
the surface, a dry cold front will be exiting the CWA with a high
moving in from Canada. By Tuesday, this ridge moves slightly east,
due to a low moving in off the coast of the Pacific Northwest, with
winds over the Northern Plains turning more northerly. By the
midweek, the ridge will be overhead with mid level winds out of the
west/southwest. Towards the end of the week, the ridge flattens as
the mid level low (from the Pacific Northwest) pushes east across
Canada/US border, switching winds to more of a zonal flow. The
surface low counterpart will also be moving west to east before the
cold front pushes through ~Thursday evening/Friday. Some variation
exists between models on exact amplitude of the ridge and
intensity/timing of the incoming low.
With this setup, mainly dry through the midweek. As this low moves
east towards the end of the week, we possibly could see some precip
but confidence remains low at this time due to model differences and
still being several days out. RH values per GFS, along with bufkit
soundings, keep the area pretty dry from ~700mb to surface, so some
of this mid level moisture could evaporate or just be light rain at
best. Probability of 24 hr QPF>0.01 indicate 10-60% chance per GEFS
Thursday-Friday, with the highest over ND/SD border. However, QPF
prob for EC, keeps the higher chances more into ND with only 10-20%
during this time along the ND/SD border. QPF>0.1 inch is 10% or less
for both models. NBM Thursday/Friday keep less than 10% of 24 hour
QPF>0.25in with most of the chances staying in ND. So this will be
something to watch for.
Highs early next week will range in the 70s/80s being seasonal
behind the cold front and incoming high. With the ridge and
southeast surface winds, we will see an increase in 850 temps
Wed/Thurs. The prob of seeing 90 degrees or over is 90-98% around
and west of the Missouri River. 50-75% chance of 90 and over across
south central SD on Thursday and 68-75% across central/south central
SD on Saturday. As the low pushes through, winds will increase
midweek. NBM Prob of gusts over 34kts will be up to 80% from
northern to central SD on Wednesday and up to 75% over the Coteau on
Thursday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 616 PM CDT Sat Aug 26 2023
Terminals KABR,KATY,KPIR,KMBG
VFR skies/vsbys are expected through tonight regionwide.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...TDK
SHORT TERM...TMT
LONG TERM...MMM
AVIATION...TDK
AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
709 PM EDT Sat Aug 26 2023
.SYNOPSIS...
A cold front slowly pushes south across the region today before
eventually stalling across far southern portions of the region
tonight. The front is then expected to slowly lift back north
Sunday through the early to middle portion of next week. This
will keep conditions a bit unsettled, especially from Sunday
night through Tuesday.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
As of 320 PM EDT Saturday...
Latest sfc analysis indicates a weak cold front draped across the
local area, becoming quasi-stationary. Aloft, WNW flow (nearly zonal)
is in place with a ridge over the western CONUS and and trough over
New England. Latest obs show temps generally in the low 90s, upper
80s on the Eastern Shore. Dewpoints in the low 70s have led to heat
indices around 100 in SE VA/NE NC. Conditions remain mostly dry
through the evening outside of isolated showers on the Eastern Shore
this afternoon. There is some uncertainty with regard to precip as
weak low pressure forms along the stalled boundary overnight,
and CAMs are not in sync. For example, HRRR maintains SCT
showers through the night that make it E of I-95 by morning
while the NAMNest is more aggressive with precip across SW
portions of the area closer to sunrise. Most agree on at least
SCT convection for areas W of I-95, so kept PoPs mostly
contained there with highest PoPs (~45%) for far western
counties. Not expecting much thunder with these, but cannot rule
out a rumble or two in the SW. Lows overnight will generally be
in the low 70s with a few spots across the NW dropping into the
upper 60s.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
As of 345 PM EDT Saturday...
The pattern still looks unsettled
Sunday/Sunday night into next week as the frontal boundary begins to
pivot back into SE portions of the area (thanks to the flow aloft
become W to WSW). Tropical Cyclone Franklin is still expected to be
well to our SE and well off the US coast Sunday, before lifting N
(and staying well offshore) Monday. The best shower and storm
chances will initially be confined to the south and southwest on
Sunday, lifting a bit further north by Sunday night. It should also
be noted that WPC has the far southern portion of the forecast area
in a Day 2 Slight (Marginal up to I-64) ERO due to the increasing
moisture (PWATs rising to 2.00"+). Latest QPF forecast shows
additional QPF Sunday through Monday ~1.00"+ across southern and
southwestern parts of the area with tapering down to ~0.50" across
far north and northeast parts of the area. A bit cooler Sunday with
highs in the low 80s in the W and mid 80s in the E. Lows Sunday
night will range from the mid 60s NW to the lower 70s SE. Similar
conditions Monday as the flow aloft becomes more WSW as the upper
trough amplifies to the W of the FA. PoPs increase from S to N
through the day Monday, resulting in likely PoPs across for most
except high chance across the north. Due to the similar conditions
to Sunday, WPC has the southern half of the forecast area in a Day 3
Marginal ERO. Highs will be held down by the clouds and onshore
flow, ranging from the low 80s SE to the mid- upper 70s N and W.
Remaining unsettled into Monday night. Low temperatures will range
from the mid to upper 60s N to to the lower 70s SE. Still looks
unsettled Tues as the boundary shifts NW, though perhaps less precip
coverage with only Chance PoPs through the day. Models continue to
show Tropical Cyclone Franklin lifting N well offshore of the SE
coast but getting shunted farther offshore by the departing trough
later Tuesday Temps will range from the Mid-70s in the NW to the mid-
80s in the SE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 345 PM EDT Saturday...
The extended period may remain unsettled as late as Wed night/early
Thursday (though uncertainty is quite high after Wed). The latest
12z/26 ECMWF/GFS still have decent agreement in the next potential
tropical system lifting N through the ern Gulf of Mexico Tue
night/Wed. Beyond that, the models diverge as the upper trough over
the NE CONUS leaves the system behind (GFS) vs. pushing it NE off
the SE US coast (ECMWF). For now will follow the blends due to the
uncertainty, keeping chc PoPs in the forecast Wednesday and Thursday
(S and SE). This will of course be subject to change as the models
get a better handle on the pattern. Wednesday also has a Marginal
ERO`s from WPC. Highs Wed will below- mid 80s, then only upper
70s/around 80F Thu- Fri.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
As of 715 PM EDT Saturday...
VFR conditions to start off the 00z TAF period. Will keep the chance
for an isolated/scattered SHRA/TSRA later this evening and into the
overnight hours. Best chance will be across the Eastern Shore and
western Piedmont. However, confidence is not high enough to put any
mention in the TAFs as of now. Guidance continues to indicate the
potential for low stratus/fog pushing in along the coast generally
after 06Z. Included the mention of MVFR/IFR CIGs for SBY and ORF
where confidence is slightly higher, though PHF and ECG may also see
some low stratus depending on exactly how far inland it reaches.
Winds will generally be light and out of the N-NE through the
period. Scattered TS will be possible again during the afternoon
hours of Sunday. Can`t rule out brief VIS reductions in any storm
that does develop.
Outlook: Unsettled conditions with a higher chc for showers and
flight restrictions later Mon-Tue.
&&
.MARINE...
As of 240 PM EDT Saturday...
Wind has become generally northeast and east this afternoon in
the wake of a weak front with seas around 3 ft and bay waves 1
to 2 ft. Overnight winds will become east to southeast and
remain rather light. Winds will become NE around 10 kt Sunday
morning then increase to 10 to 15 kt with gusts up to 20 kt
later Sunday into Sunday night as the pressure gradient tightens
along the coast with high pressure to the north and a weak
surface trough to the south. NE flow with winds of 15 to 20 kt
will persist through Mon aftn, as sfc high pressure will be
sitting N of the local area, and a tropical system (Franklin)
will be moving NNE well east of the SE and Mid Atlc coast. Swell
waves from Franklin are expected to impact the local waters Mon
aftn through Wed. At this time, expecting seas to peak at 5-7ft
through the day Tuesday and into the first half of Wednesday.
Moderate rip current risk will continue through the weekend.
Rip risk remain moderate Monday for VA Beach and NC, but high at
Ocean City. Rip risk will increase Monday and likely be high
along all area beaches Tue and Wed with dangerous surf likely.
Another area of low pressure originating as a tropical system
developing in the Gulf of Mexico will lift northeast potentially
tracking just inland or along the Carolina coast. This likely
will impact our marine weather later next week. Winds and seas
build early Thursday morning. Northeast winds of 15 to 25 kt and
potentially stronger are likely Thu and Fri next week along
with rapidly building seas.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...None.
&&
$$
SYNOPSIS...AJB
NEAR TERM...AM
SHORT TERM...AJB/AM
LONG TERM...AJB/AM
AVIATION...AM/JKP
MARINE...TMG/JAO
Area Forecast Discussion
National Weather Service Boston/Norton MA
1056 PM EDT Sat Aug 26 2023
.SYNOPSIS...
Dry and seasonable Sunday and Monday. A stalled frontal boundary
just offshore combined with moisture from distant Hurricane
Franklin may bring a soaking rain to southeast New England
Tuesday and Wednesday. High surf and rip currents for south-
facing beaches is also possible. High pressure leads to dry
weather for Thursday into Saturday, however we will need to be
monitoring for storminess near the Carolina coast.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
Showers continued to dissipate this evening across southern New
England. Thinking the rest of tonight remains dry for most of
our region. Still trying to get a good handle on when and if
marine stratus advects onshore. Not seeing many signs over the
Gulf of ME on satellite yet, but there does appear to be stratus
over Stellwagen Bank, just east of the Cape and across
Nantucket.
Minor tweaks to temperatures to reflect observed trends.
810 PM Update:
Scattered showers with limited vertical depth moving SE through
west-central MA; these showers heralded the leading edge of
a cold front with lower dewpoints behind it across interior
northern New England. Drier air aloft has kept these showers
from developing much vertically, and these showers are
gradually losing potency now that we`re after sundown, with
further weakening anticipated before dissipating in entirety by
10 PM. These certainly could wet the ground but expect these
showers to be brief and passing. Edited the forecast to show 20%
PoP for isolated SHRA thru 02z mainly along and north of the
Mass Pike.
Thereafter ridging builds in from the northwest with lowering
dewpoints into the lower to mid 60s. Forecast challenge for the
latter half of the evening into the early Sunday morning period
is the coverage and extent of returning stratus from the layer
of clouds well offshore, in which a fair majority of guidance
looks to return back landward as sfc flow turns NNE to NE. Is it
believable is the question. The moisture layer has also made
quite a distance offshore, though the southern end of it is
bringing fog and stratus to Nantucket. Thinking the soonest this
may return back westward is well after midnight; but I`m also
pretty skeptical it makes it as far back landward as far as the
guidance suggests it will with southeastern MA and coastal areas
standing the best chance at seeing this low cloud layer making
it back westward. Will have to monitor obs and incoming 00z
guidance.
Previous discussion:
Quiet across southern New England at the moment, as mid level
dry air along with a layer of warmer air is keeping convection
from developing. Still anticipate some of the shallow convective
showers to skim across northern MA through mid evening, per
latest HRRR runs. No thunder is expected, and any showers will
be rather brief. The threat of any showers will be gone by 10pm,
if not a bit earlier.
Otherwise the primary aspect of the overnight forecast revolves
around the expected shift in wind direction to the NNE after
midnight. Quite a bit of guidance suggests that with the wind
shift, we will see widespread stratus develop as the cooler air
from the Gulf of Maine advects southward. Although visible
satellite does not show much in the way of stratus at the
current time, this should change as that cool/moist air starts
moving over the warmer waters just east of southern New England.
Some guidance is also showing locally dense fog developing,
however feel that is overdone, however visibilities down as low
as 1 mile are quite possible, especially closer to the east
coast where some drizzle may develop.
As you work your way west of roughly a ORH-PVD line, it should
work out to be a mostly clear night. Perhaps some patchy fog.
Stuck to the guidance blend for lows across the region, so
generally upper 50s to lower 60s.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
320 pm update...
Onshore NE flow will continue for much of the day. At the very
least, that will keep it cooler across eastern sections (highs
perhaps barely making 70f at the immediate coast), while more
sun across the western half of SNE will push temperatures well
into the 70s.
A good amount of uncertainty as to how far west the onshore flow
will push the low clouds, how solid of an overcast they will
make and lastly how long it will take before they start to break
up. Like it or not, we are quickly getting past the time of the
year where the sun is strong to really help mix the boundary
layer. I did take a blended model approach to the sky cover
forecast which keeps things fairly cloudy across the eastern
third of the area until 2pm or so -- with some breaks finally
happening after that time. However, it`s possible the clouds
will last longer than anticipated.
12z CAMs also suggest that along the low cloud/no low cloud
boundary which will be somewhere across Central MA into eastern
CT, there will be enough differential heating to have a few
light showers develop given marginal low level moisture
profiles. Have painted in some 15-20% PoPs for that possibility.
Sunday night it does appear the onshore NE flow starts to
weaken, so suspect that clouds will slowly clear. Otherwise it
will be dry. Lows will generally be in the 50s across all of
SNE.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
315 pm update...
Highlights:
* A stalled frontal boundary interacting with tropical moisture from
distant tropical cyclone Franklin may bring rain (perhaps locally
heavy?) to SE New England Tue and Wed although there is
uncertainty on this.
* High surf and rip currents on south facing beaches expected Tue
and Wed as long period swell from Franklin moves northward.
* Cooler, blustery and much drier Wed night.
* Nice stretch of weather Thu-Sat, although monitoring tropical
developments in the Caribbean/Gulf of Mexico that may move into
the Carolinas later next week.
Details:
Monday:
Sfc ridge of high pressure will still be established during the
daytime hrs Mon. South of the ridge over the far southern outer
waters will be a stalled frontal boundary. This frontal boundary`s
exact position is still somewhat uncertain but it should stay far
enough to the south for dry weather. However increasing S/SW flow
later in the day, in response to a digging upper trough over the Gt
Lakes, should at least bring increasing clouds from S to N as the
day goes on, tending more concentrated in southern areas with less
further north.
Monday Night Through Wednesday:
This period looks to be the more active in the long-term forecast
period, as tropical moisture associated with TC Franklin interacts
to various extent (as depicted across models/ensembles) with a
stationary front and the aforementioned upper trough and associated
mid/upper jetstreaks. Besides rainy conditions, long period swells
from Franklin`s center should begin across our southern-exposed
beaches by Mon evening, but wave heights steadily increase and peak
by Tues and Wed with the potential for at least a day to two days of
high surf/rip currents to south-facing beaches. For the latest on
Franklin, see the latest advisories from the National Hurricane
Center. In sum the two greatest threats, in order of certainty,
appears to be from high surf/rip currents and then rain.
There is still a considerable amt of uncertainty on PoP/QPF in this
period, and that has to do with the interplay of a few things. One
is the strength of the upper-level forcing/amplitude of the trough
over the Gt Lakes region. Next is the position and location of the
stationary boundary, which should retreat northward to some various
extent as llvl SE flow increases in response to Franklin`s closest
pass. Last but not least is the strength and track of Franklin
itself, which latest forecasts call to pass well SE of the New
England waters. On rain amts, the GFS and its ensemble GEFS output
are essentially a shutout entirely as the boundary lies too far
south/offshore to permit any rain from making it landward. On the
other hand the ECMWF is quite wet starting early Tues and into Wed
especially over southeast New England (its ensemble, EPS, probs of 1
inch of QPF in a 24 hr period Tue into early Wed show solid 40-60%
probs in SE MA/Cape and Islands, much less to nil north of I-95,
with deterministic ECWMF showing some 2-3 inch rain amts). The
Canadian on the other hand is a middle ground between the two. So
the outcomes range from essentially nil to a soaking rain for SE New
England, so quite a bit of uncertainty still exists. It`s far from a
perfect analog to a predecessor rain event and would be hasty
to call it such, since Franklin will be passing well to our
southeast, but does share some of the same large-scale
ingredients to one (e.g. tropical moisture interacting with a
jetstreak poleward of the tropical cyclone). If the ECMWF/GEM
solutions verify, shouldn`t see thunder from this, although some
thunder is possible in interior New England on Wed as the upper
trough passes through. Will need to monitor developments
closely but for now I`ve left PoP at chance levels, higher end
of Chance in SE New England Tue/Tue night and early Wed.
As mentioned, long period (10-14 sec pd) waves/swell from Franklin`s
passage will bring the potential for rip currents and high surf to
southern facing beaches and that will at least be one weather-
related risk we`ll need to message. Too early yet for rip current
statements or possible high surf advisories but rip current/surf-
related headlines seem likely to be needed per ECMWF Wave and
WaveWatch II guidance.
Overall a cloudier-than-not period regardless, with highs in the 70s
tending lower in our southern areas, lows in the low mid 60s.
Wednesday Night:
Seasonably strong 1020+ mb high pressure ridges in Wed night. With
it will bring rather breezy N/NW winds and much cooler/drier air.
Should see both decreasing clouds but also much lower, more
comfortable dewpoints in the 40s to lower 50s. Northerly winds may
reach into the 15 to 20 mph range for a time overnight, and a
possible window for small craft advisories on all waters. 925 mb
temps fall around +10 to +13C range; lows falling into the upper 40s
to the mid 50s (upper 50s Cape and Islands).
Thursday through Saturday:
Looks relatively quiet as strong high pressure settles over SNE. For
now, anticipating a few days of dry weather with abundant sun and
clear nights with seasonable temps. Going to have to still watch
developments in the tropics and Gulf of Mexico/Carolinas vicinity
regarding an area of disturbed weather in the Caribbean/southern
Gulf of Mexico, but for now opted for dry weather.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
Forecast Confidence Levels:
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Moderate confidence.
VFR through at least 05z for many, with winds becoming NNE to
NE late tonight. As this occurs, stratus well offshore looks to
return back landward, though its western extent is still a bit
uncertain. Lowest conditions further SE you go (IFR or lower for
PVD and the Cape airports), with BKN- OVC MVFR for BOS-BED-ORH.
These MVFR to marginal IFR conditions will be slow to dissipate
tomorrow given continued onshore flow. Perhaps even slower than
currently forecast. The western half of the forecast area should
remain VFR for tomorrow. Small chance of an afternoon shower
around ORH.
KBOS TAF...Moderate confidence in TAF. VFR through at least 07z
with winds becoming light NE; stratus lurking offshore may
return back westward but uncertainty continues on how far west
it gets and if cigs become IFR. Left as BKN MVFR but will need
to monitor trends and incoming guidance given the uncertainty.
KBDL TAF...High confidence in TAF. Primary aspect of
uncertainty will be area of MVFR to IFR ceilings that will
spread westward from the Atlantic late tonight and tomorrow.
Don`t think they will get as far west as BDL, but later
forecasts will look at that aspect.
Outlook /Monday through Thursday/...
Sunday Night through Monday: VFR.
Monday Night: VFR. Slight chance SHRA.
Tuesday: VFR. Chance SHRA.
Tuesday Night: Mainly VFR, with local MVFR possible. Chance
SHRA.
Wednesday: Mainly VFR, with local MVFR possible. Breezy. Chance
SHRA.
&&
.MARINE...
Forecaster Confidence Levels:
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
320 pm update....
Overall High Confidence.
Winds and seas have fallen below Small Craft Advisory thresholds
as of early this afternoon, and all SCA headlines have been
taken down. Not looking at any strong winds through Sunday
night. We will have a wind shift late tonight, with light W/NW
winds becoming N/NE. As that happens, we should see clouds and
areas of fog develop. Could be some locally dense fog across the
waters especially east of the Cape and down around the Islands.
This marine fog will last for much of Sunday and into Sunday
evening.
For awareness purposes, we are expecting some long period swells
from Hurricane Franklin to be getting into the coastal waters
later Tuesday into Wednesday. Periods of 12 to 14 seconds are
currently forecast, along with swell heights near 7 feet,
especially across the waters south of New England. Please
continue to monitor later forecasts.
Outlook /Monday through Thursday/...
Sunday Night through Monday: Winds less than 25 kt.
Monday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Slight chance of rain showers.
Tuesday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Chance of rain showers.
Tuesday Night: Winds less than 25 kt. Local rough seas. Chance
of rain showers.
Wednesday: Winds less than 25 kt. Areas of rough seas. Chance
of rain showers.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...None.
&&
$$
SYNOPSIS...Loconto/Nash
NEAR TERM...Belk/Loconto/Nash
SHORT TERM...Nash
LONG TERM...Loconto
AVIATION...Loconto/Nash
MARINE...Loconto/Nash
Area Forecast Discussion...Updated
National Weather Service Billings MT
846 PM MDT Sat Aug 26 2023
.UPDATE...
A few weak showers and thunderstorms formed over the mountains
and foothills late this afternoon and early this evening. The
activity weakened as it moved off the mountains with less
instability and shear available. Stronger energy was lurking back
into central Idaho and progged to round the ridge axis in place
this evening and tonight, and move into western and central zones.
Lowered PoPs quite a bit over western and central zones for
tonight, but did leave some in place given the wave expected. This
wave will push a boundary through the area toward morning and
this could be the focus for more showers developing in the morning
hours over western and central zones. Adjusted accordingly. TWH
&&
.DISCUSSION...
Through Sunday night...
The Northern Rockies will be under the periphery of an upper
ridge through most of Sunday. Weak upper air disturbances will
move through the flow and produce isolated to scattered showers
and thunderstorms (20-60% chance) over south central MT and north
central WY this afternoon and tonight. Precipitable water values
of about 0.80-1.10 inches over our area and HRRR model data
indicate that thunderstorms could produce brief downpours and wind
gusts to about 40 mph.
On Sunday, the upper flow will evolve with an upper air shortwave
trough moving southeastward over MT which will bring increased
support for scattered showers and thunderstorms over the same
area, SC MT and NC WY, including Billings. This wave will also
bring a weak cold front southwestward over the area, with drier
air moving in from the northeast and aloft. Showers and
thunderstorms are likely in the mountains and foothills (50-70%
chance) but have a lower though still appreciable chance of
occurring in the lower elevations of south central MT, including
Billings, at 20-40%. Thunderstorms again could produce downpours
and gusty winds.
Sunday night, shower/storm activity should exit the area to the
southeast as the shortwave trough continues its southeastward
movement.
Low temperatures will generally be in the 50s to lower 60s tonight
and Sunday night. High temperatures will mainly be in the 80s. RMS
Monday through Friday...
A ridge of high pressure over the region will prevail through
Tuesday leading to dry and very warm conditions. Tuesday night
into Wednesday, a Pacific shortwave trough is still progged to
push a cold front through the area. Models are in agreement that
most of the associated precipitation will remain west of Billings
as the main forcing tracks northwest of our CWA, but look for
isolated to scattered showers/thunderstorms possible over our
western zones Tuesday evening. Our main concern is how much the
windy conditions and drying downslope flow may elevate fire
weather risks for Wednesday...something we will be monitoring as
we approach midweek.
High temperatures will be in the 80s to around 90 Monday, then
peak in the upper 80s/lower 90s Tuesday before cooling somewhat
behind for Wednesday and the remainder of the week. BT
&&
.AVIATION...
A few showers and isolated thunderstorms will linger through the
night into Sunday morning over western and central zones. Showers
and thunderstorms are possible into Sunday afternoon, mainly south
and west of a line from Harlowton to Billings to Ashland.
Activity on Sunday could produce locally heavy rainfall (brief
MVFR conditions) and gusty winds. Otherwise, VFR conditions are
expected tonight and Sunday. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
Sun Mon Tue Wed Thu Fri Sat
-----------------------------------------------------------
BIL 062/086 059/088 059/092 063/085 054/083 055/085 059/089
22/W 10/U 00/U 10/U 00/U 00/B 11/U
LVM 056/084 052/085 054/089 053/079 047/079 049/080 053/084
26/T 21/U 00/U 31/N 00/U 01/B 11/U
HDN 059/087 056/088 054/093 060/087 051/084 051/087 055/090
12/W 10/U 00/U 00/U 00/U 00/U 10/U
MLS 061/088 057/087 057/090 065/086 055/083 056/086 060/089
00/U 00/U 00/U 00/U 10/U 00/U 10/U
4BQ 064/088 059/087 057/091 065/088 054/084 055/088 060/089
10/B 10/U 00/U 00/U 10/U 10/U 10/U
BHK 059/086 054/084 054/087 060/086 052/082 054/083 056/086
00/U 00/U 00/U 00/U 10/N 10/U 10/U
SHR 058/081 054/083 052/088 057/085 050/082 051/085 055/086
25/T 31/U 00/U 00/U 00/U 10/U 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...None.
WY...None.
&&
$$
weather.gov/billings
Area Forecast Discussion
National Weather Service Cheyenne WY
941 PM MDT Sat Aug 26 2023
.UPDATE...
Issued at 932 PM MDT Sat Aug 26 2023
The forecast remains on track this evening and overnight as
residual light rain showers have all but ended near sunset.
Overnight lows will remain mild, in the 40s across the higher
terrain, and low to middle 50s for a majority of the remaining
cwa. Rain showers are not expected to re-develop across the area
ahead of our next shortwave disturbance that will approach the
region tomorrow with another round of potentially active weather.
Valley areas may see some patchy fog near daybreak, but the dense
fog that was present across the I-80 Summit is not expected to
occur between now and daybreak tomorrow morning. Overall, a quiet
night is in store for the region, before we transition to a shift
in the weather pattern by tomorrow afternoon.
&&
.SHORT TERM...(This evening through Monday night)
Issued at 300 PM MDT Sat Aug 26 2023
Current surface analysis depicts high pressure slowly migrating
eastward into the Midwest, as the weak cold front continues to dig
south of the Great Lakes and a shortwave tracks east through central
Wyoming.
Showery actively is expected to continue throughout the next few
days, with some shortwave disturbances expected to cut through the
area and kicking up some convection along the way. While there could
be some activity this afternoon and evening, the eastward propagation
of the slow moving ridge axis towards the Intermountain West will
effectively cut off any additional moisture advection into the
region. Therefore, the shortwave currently located across central
Wyoming will be limited to the pre-existing and lingering low-
level moisture and primarily keeping most precipitation chances
across the higher terrains with areas to the east under more
downsloping flow.
Into tomorrow, the upper level ridge is expected to retrograde back
to the west, producing primarily northwesterly flow across north
to north-central CONUS and allowing a more robust shortwave
to dig across the CWA. Under this flow regime, better moisture
advection across the region will aid in the production of
afternoon showers and thunderstorms along the Laramie Range and
traveling to the east in to the Nebraska Panhandle by the late
afternoon to evening hours. HiRes model guidance has been trending
this precipitation upwards, with a line of activity forming
around 20z and gaining momentum as it pushes to the southeast.
Thermodynamic profiles are also starting to come into better
alignment for stronger storms with the RAP showing pockets of
higher MUCAPE around 1300 J/kg to 1800 J/kg, and decent 700 to
500mb lapse rates hovering around 8.3C/km, stretching across
Platte/Goshen County and extending into a good portion of the
Nebraska Panhandle. Main concerns is going to be with the shear,
with the forecast soundings keeping EBWD at 30 knots or lower,
even with the arrival of the upper level jet energy creating
veering wind profiles. Will continue to keep the severe
thunderstorms potentials low, with brief periods of heavy rainfall
possible, in addition to the potential for small hail and strong
winds associated with stronger storms.
Continued uncertainty exists for Monday, with the placement of the
upper level ridge being the deciding factor for either a dry or wet
forecast. Current GFS and Euro deterministic models vary slightly,
with the Euro placing better QPF for the early morning hours,
continuing Sundays precipitation through the overnight hours and the
ridge axis shifting into place cutting off precipitation chances
through the remainder of the day. On the opposite end, the GFS
proposes a brief break in the weather and the return of afternoon
showers and thunderstorms with good low-level moisture, northwest
flow, and daytime heating playing a role. Started making adjustments
to the PoPs to account for the uncertainty in both solutions, with
tomorrow`s precipitation playing a big role in how quickly storms
dissipate Sunday morning.
.LONG TERM...(Tuesday through Saturday)
Issued at 300 PM MDT Sat Aug 26 2023
Upper ridge axis builds over Wyoming starting off Tuesday ahead of
a low pressure system moving into Oregon and western Idaho. Ridge
axis passes overhead Tuesday afternoon as low tracks northeast
into western Montana. ECMWF shows some low qpf over the south
Laramie Range Tuesday afternoon. So did add some slight chance
PoPs briefly Tuesday afternoon.
Could be breezy Wednesday and Thursday as the upper low tracks
across Montana. 700mb winds up near 30-35kts...so expect breezy
conditions Wednesday. Warm and dry conditions expected across the
CWA with highs ranging from the low 80s west of the Laramie Range
to the low 90s in the Panhandle. Elevated to critical fire weather
conditions possible for those fire weather zones that are reported
YES on fuels.
Begin to see an increase in showers and thunderstorms Friday as
next ridge axis begins to build over Wyoming. These showers/storms
look to be confined to areas west of the Laramie Range Friday
afternoon as moisture from the southwest moves into the area.
PWATS up near .9 inch across Carbon County. Showers/storms again
possible for Saturday afternoon across the same areas.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 530 PM MDT Sat Aug 26 2023
Mainly VFR expected for the forecast period. Clearing skies
expected for most of the area overnight with light winds
generally out of the south. More widespread PM shower and
thunderstorm activity is likely Sunday, starting west and
spreading east towards the end of the TAF period. Added in VCTS
for most locations. Storms may produce brief heavy rainfall and
gusty winds.
&&
.FIRE WEATHER...
Issued at 300 PM MDT Sat Aug 26 2023
Little fire weather concerns through Tuesday, with minimum RH
values staying above critical thresholds due to recent wetting
rains. Hot and dry conditions expected by midweek will inevitably
raise fire weather concerns as the minimum RH values drop to the
mid-teens for much of the western counties and gusty winds
expected both Wednesday and Thursday.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
UPDATE...BW
SHORT TERM...MRD
LONG TERM...GCC
AVIATION...MN
FIRE WEATHER...MRD
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1053 PM EDT Sat Aug 26 2023
.SYNOPSIS...
Lingering showers and thunderstorms possible through midnight
tonight. A frontal boundary will bring cooler temperatures below
normal through the period. Heavy rainfall likely Sunday through
Tuesday. Mid to late week weather remains uncertain due to the
potential for a tropical system to develop Gulf of Mexico.
&&
.NEAR TERM /THROUGH SUNDAY/...
As of 1045 PM Saturday: Strong to severe thunderstorms moving
through the CLT Metro area. Most CAMs have this activity dissipating
by 06Z or so. The untapped environment lead to late evening severe
thunderstorms. A few isolated showers are popping up in the
Upstate as well. Kept a PoP mention into the early overnight hours.
Otherwise, the overnight still looks mostly dry and tweaked the
forecast based on trends and current observations.
The boundary should settle to the south of the CWA by Sunday,
bringing in cooler temps. Meanwhile, the upper ridge begins to
retrograde westward, allowing for upper flow to move southward from
the upper Great Lakes. This developing trough will swing through the
area with another boundary that should stall just to the south of
the region on Sunday morning. More S/SE surface and mid-level flow
should draw in additional moisture, setting the stage for a wetter
pattern from the end of this forecast period into the next. At this
point, showers and thunderstorms are likely Sunday afternoon, after
2PM. The enviroment remains primed to support widespread showers and
thunderstorms with 2000 J/kg of SBCAPE, PWATS approaching 2.5
inches, and an enhanced are of DPVA embedded within the trough.
Therefore, categorical PoPs across the NC Mountains and widespread
through the NC/SC Piedmonts. Confidence is increasing on heavy
rainfall with local impacts of isolated flooding, especially in
urban areas for Sunday. Again, this event will stretch beyond
Sunday, into the work week, with additional rainfall anticipated.
Currently 2-4 inches from Saturday evening through Tuesday morning,
with totals subject to change depending on where storms form and
train. As for temperatures, expect low 90s and upper 80s for the
highs and low 70s for Saturday night.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
As of 2:25pm EDT Saturday: Monday and Tuesday will see mostly
cloudy conditions and continued height falls, leading to highs in
the mid 80s most areas to upper 70s in the higher terrain areas.
Dewpoints will remain strong, though, so morning lows will still be
5 or more degrees above normal. Broad trough will persist over the
eastern CONUS with numerous shortwaves transiting the region that
will help to realize the 2" plus PWAT values Monday and Tuesday
afternoons. Overall synoptic forcing is on the weak side as most
energy with the trough is well north, leading to a strong diurnal
signal in convection, as well as light surface winds. Shear will be
weak as well, topping out at 25kts on Monday and Tuesday. CAPE is
likewise underwhelming with model soundings showing SBCAPE around
1000 j/kg. Severe weather is, thus, not a huge concern with short-
lived cells the dominant mode.
Total rain through Tuesday might average around 2", which by itself
will not trigger major hydro concerns, but this will serve to
saturate the surface, setting things up for more sensitive runoff
potential later in the week.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 2:45pm EDT Saturday: Extended forecast will be largely
determined by large uncertainty regarding potential Gulf tropical
system. NHC has a large chance of a tropical system forming in the
Eastern Gulf over the next couple of days, but models vary quite a
bit on the path of this potential system. GFS persists in putting
the storm much further north than other models, with possibly heavy
rain Wednesday night into Friday, while EC and Canadian models have
the system tracking more along the coast with potentially very
limited rainfall inland. Models tend to agree, though, that once
this tropical system is past, POP declines considerably. Hydro
concerns remain an area to watch as moderate precipitation earlier
in the weak will create antecedent conditions for significant hydro
concerns, should something like the GFS precipitation forecast
verifies.
Continued cloudy and rainy conditions through the extended will
limit temps with highs down into the 70s, rebounding on Saturday as
trough/tropical system passes and a mid-level ridge replaces it.
Depending on path of tropical system, winds could be elevated with
its passage, particularly on Thursday.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
At KCLT and elsewhere: Mostly VFR conditions at all terminals
through Sunday morning. A few thunderstorms are ongoing over KCLT
and have placed a TEMPO for TSRA and associated restrictions through
04Z. A few showers are still possible at the Upstate terminals.
Mountain valley fog/low stratus can`t be ruled out and gave KAVL a
mention for possible restrictions, but confidence is not as high
that fog/low stratus will work that far into the French Broad
Valley. The RAP has shown a deck of low stratus developing in the
CLT Metro, where most of the rain in the CFWA has fallen this
afternoon. Confidence was too low for a mention, but definitely
worth a blurb in the AFD. Otherwise, a cold front will sag into the
area from the north and stall in the Upstate. This will result
numerous showers and thunderstorms across the area starting Sunday
afternoon. Tried to depict the onset time and associated
restrictions with a PROB30, followed by a -SHRA VCTS prevailing line
through the end of the forecast period. Model guidance continue to
produce lingering showers and embedded thunderstorms over the
terminals into Sunday night.
Outlook: Shower and thunderstorm chances continue Sunday into early
next week as a cold front remains stalled south and east of the
forecast area. Mountain valley fog and low stratus development will
remain possible each morning around daybreak.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
SYNOPSIS...CAC/CP
NEAR TERM...CAC/CP
SHORT TERM...WJM
LONG TERM...WJM
AVIATION...CAC
Area Forecast Discussion
National Weather Service Houston/Galveston TX
633 PM CDT Sat Aug 26 2023
...New AVIATION...
.SHORT TERM...
(This evening through Sunday Night)
Issued at 318 PM CDT Sat Aug 26 2023
Tis a hot afternoon on this National Dog Day. Most inland areas
are in the triple digits once again with temps well into the 90s
at the coast. Perhaps fetch is better played indoors or at least
not until later this evening when temperatures aren`t as hot. Make
sure you and your dog(s) are well hydrated. Also check the
pavement to make sure it`s not too hot for your furry friend`s
paws. A burned paw is a terrible gift for a canine on this
National Dog Day. Like yesterday, we cannot rule out isolated
shower or thunderstorm activity. Unlike yesterday, there appears
to be less diurnal cumulus development, thus, fewer signs that the
atmosphere is trying to bestow upon you and your dog a much
needed rain shower. If this heat is bothering you, then you will
not like this next paragraph.
Tomorrow`s temperatures look interesting to say the least. A
strong mid/upper ridge centered near the Texas / New Mexico
border will continue its westward progression. The resulting
changed in the regional flow pattern will advect warmer
temperatures aloft, currently to our north, into southeast Texas.
850mb temps could possible warm into the upper-20s centigrade,
particularly north of I-10. This could easily translate to
widespread 105+ temps over inland areas (including interior
coastal counties) as the near surface atmosphere mixes with the
toasty atmospheric layers aloft. In addition, a weak frontal
boundary will approaching the area from the north. Westerly flow
coupled with compression ahead of the front could boost
temperatures even further. However, this front does add an ounce
of complexity to the forecast.
Capping will weaken somewhat tomorrow as the ridge pushes
westward. The addition of frontal lift and modest PVA into the
region is expected to be enough to spark isolated to scattered
showers and thunderstorms. If this were to occur early enough,
then the front could save us from challenging all-time records.
If not, then some inland areas will likely approach 110F again!
That is very dangerous heat and certainly too hot to take part in
Crab Soup Day (everyday is a holiday).
There is one other feature worth mentioning. A subtle shortwave
can be seen over southwestern Kansas via water vapor imagery and
RAP 500mb analysis. The steering flow should take this shortave
into either southeast Texas or Louisiana by tomorrow night. GFS
and ECMWF both initialize this shortwave decently well but show
differing solutions. GFS keeps it pretty weak and while the ECMWF
shows a more robust disturbance. As you can imagine, the more
robust solution is showing a better chance of showers and
thunderstorms overnight Sunday. If mother nature is going to turn
up the furnace tomorrow, then the least it could do is give us
some rain late Sunday.
Self
&&
.LONG TERM...
(Monday through next Friday)
Issued at 318 PM CDT Sat Aug 26 2023
The aforementioned weak frontal boundary will continue to push south
towards the coast on Monday. Global models show hints of the
afternoon sea breeze attempting to thwart it`s southern progression,
but pushing offshore regardless and becoming quasi-stationary over
the Gulf of Mexico. Weak capping, support from shortwave impulses
and 1.8-2.1" PWs are enough to support scattered storm development
throughout the day, so any mesocale boundary interactions (like with
the sea breeze) should further enhance rain chances during the day.
Any showers/storms that develop should provide relief from the
oppressive heat. Locations that don`t receive rainfall may still see
triple digit highs on Monday. Thankfully, reduced subsidence,
decreased 850mb temperatures, lower moisture and offshore flow
should work to bring some substantial relief heat-wise in the days
following. Even with decreasing rain chances, highs for Tuesday and
onwards look to be in the 90s to lower 100s with heat indicies under
106 degrees. Lows should be in the 70s to lower 80s.
On Wednesday, a weak midlevel trough axis looks to dive south across
the Plains into SE Texas. PWs slipping under 1.4" and dry conditions
in the lowers levels don`t bode well for getting much in the way of
measurable rainfall for Wednesday. Regardless, current guidance
keeps this trough looming over the coastal bend, becoming a weak
midlevel low on Thursday. This feature aims to increase rain chances
during the later half of next week, though uncertainty remains as to
how this feature will evolve. Onshore flow develops Thursday
night/Friday morning, ushering in moisture return and gradual
warming through the end of the week.
03
&&
.AVIATION...
(00Z TAF Issuance)
Issued at 621 PM CDT Sat Aug 26 2023
Mostly VFR conditions expected through the end of the TAF period.
There`s a chance for MVFR cigs/vis again for LBX/SGR/GLS as well
as patchy fog possible for LBX/SGR before sunrise Sun morning.
Fog, if any, is expected to quickly burn off by around 14Z. Light
and VRB winds expected overnight, then winds turn W-SW and
strengthen to 06-10 KTS around sunrise. Iso SH/TS are possible Sun
afternoon and evening across portions of SE TX as a weak frontal
boundary pushes into the local area from the north. Began the
mention of VCSH/VCTS on this TAF issuance, however, confidence of
how strong/widespread activity will be and whether storms will
make it into IAH southward, remains low at this time. Will
continue to assess the upcoming Hi-Res solutions and modify if
needed.
Cotto (24)
&&
.MARINE...
Issued at 318 PM CDT Sat Aug 26 2023
Light to moderate, sea and land breeze driven winds are expected
over the weekend. Rain chances increase on Monday as a weak frontal
boundary pushes southward towards the coastline, later pushing
offshore on Tuesday. Rain chances decrease mid next week while the
sea-land breeze circulation resumes.
&&
.FIRE WEATHER...
Issued at 318 PM CDT Sat Aug 26 2023
Very hot and dry conditions are expected ahead of an approaching frontal
boundary on Sunday. By late afternoon and evening, the front is expected
to make the environment increasingly favorable for isolated to scattered
showers and thunderstorms, especially over our northern counties. Relative
humidity values are expected drop into the 20 to 30 percent range in the
afternoon. We will need to monitor winds near the coast that
could push conditions into Red Flag criteria for our coastal
counties.
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 79 107 79 100 / 0 40 40 50
Houston (IAH) 80 107 82 102 / 0 30 40 60
Galveston (GLS) 80 97 83 94 / 0 10 20 50
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Excessive Heat Warning until 10 PM CDT Sunday for TXZ163-164-
176>179-195>200-210>213-226-227.
Heat Advisory until 10 PM CDT Sunday for TXZ214-335>338-436>439.
Heat Advisory until 10 AM CDT Sunday for TXZ235>238-300-313.
Excessive Heat Warning from 10 AM to 10 PM CDT Sunday for
TXZ235>238-300-313.
GM...None.
&&
$$
SHORT TERM...Self
LONG TERM....03
AVIATION...24
MARINE...03
Area Forecast Discussion...UPDATED
National Weather Service North Platte NE
614 PM CDT Sat Aug 26 2023
...Aviation Update...
.SYNOPSIS...
Issued at 350 PM CDT Sat Aug 26 2023
Key Messages:
-Chances for precipitation will increase Sunday night across the
west.
-Mainly dry conditions are expected for the remainder of next week
with temperatures trending into the 90s by midweek.
H5 analysis this morning had an elongated area of high pressure
centered over eastern New Mexico. Ridging extended north of the
high`s center into southern Montana. West of the high, closed low
pressure was located approximately 500 miles off the southern coast
of Oregon. On the northern periphery of the high, a shortwave was
noted over northeastern Kansas. Across southern Canada, a trough
extended from Quebec south into New England. A tandem of shortwaves
were noted over southwestern Canada, the first over southern
Saskatchewan and a second over southern British Columbia. At the
surface, a cold front extended from southwestern Oklahoma, northeast
into central Illinois and northern Indiana. North of this cold
front, high pressure was anchored over south central Canada and the
Dakotas. Skies were mostly clear this afternoon and 2 PM CT
temperatures ranged from 73 degrees at O`Neill to 80 degrees at
Imperial.
&&
.SHORT TERM...(This evening through Sunday night)
Issued at 350 PM CDT Sat Aug 26 2023
In the near term, the main forecast challenges are temperatures
tonight, then precipitation chances Sunday night. For tonight,
surface high pressure will build into the upper Mississippi Valley
from the Dakotas. Winds will be light from the east this evening,
shifting to the southeast overnight. Dry air and clear skies will
facilitate a quick cool down this evening. Looking at guidance
temps for tonight, the NBM is the warmest with the MET guidance
the coolest. Looking at the GFS, NAM12 solns and MET guidance this
morning, they initialized too dry with their sfc dew points. With
this in mind, decided to trend my lows tonight toward the warmer
NBM guidance. This resulted in lows in the lower 50s across the
area. A weak frontal boundary will approach northwestern Nebraska
late in the day Sunday. South of this feature, weak warm air
advection and southerly winds will push temps into the 80s Sunday
afternoon. Wouldn`t be surprised to see some readings around 90
over far northern areas in closest proximity to the approaching
cold front. The frontal boundary will track south into western
Nebraska Sunday evening, exiting the forecast area Monday morning.
As this feature tracks through the area, a weak upper level
disturbance, embedded in northwesterly mid level flow aloft, will
approach the Panhandle, then track into southwestern Nebraska
overnight. The CAMS along with the latest GFS and NAM12 soln
develop some light precipitation in the Panhandle Sunday evening,
gradually forcing this southeast into far southwestern Nebraska
Monday morning. With this forecast package, went ahead and trended
precipitation chances upward in the eastern and southeastern
Panhandle based on decent spatial agreement with their
precipitation fields in the NAM12 and HRRR this morning.
.LONG TERM...(Monday through Saturday)
Issued at 350 PM CDT Sat Aug 26 2023
After a slight cool down for Monday, readings will rebound back
into the mid to upper 80s Tuesday and Wednesday, followed by 90s
for Thursday through Saturday. Ridging across the west will
transition east onto the central Plains midweek next week leading
to the warmup. Toward the end of the week, we may see a frontal
passage possibly Thursday night into Friday which may lead to
cooler temps and increased precipitation chances. ATTM there is
not much consistency with this feature between the EC and GFS
solns. With that in mind, stuck to the NBM forecast with this zone
forecast package.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 609 PM CDT Sat Aug 26 2023
Clear skies and dry air will remain across wrn and ncntl Nebraska
tonight through early Sunday aftn. The risk of VFR or lower
flight conditions during this time is very low, near zero.
A weak cold front will move into nrn Nebraska 21z-00z Sunday
afternoon. The front could be the focus for isolated thunderstorms
affecting areas along or north of highway 2. There are no flight
concerns south of highway 2 during this time.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Buttler
SHORT TERM...Buttler
LONG TERM...Buttler
AVIATION...CDC
Area Forecast Discussion
National Weather Service Lubbock TX
625 PM CDT Sat Aug 26 2023
...New AVIATION...
.SHORT TERM...
(This evening through Sunday)
Issued at 255 PM CDT Sat Aug 26 2023
Water vapor imagery currently shows an upper level ridge over the
Desert Southwest with a plume of modified monsoonal moisture
stretching from the central Great Plains southwestward into northern
Mexico. Steering flow remains weak around the forecast area and this
was observed on the 12Z upper air maps. At the surface, the cold
front remains positioned along the I-10 corridor and bending
northward into the TX Big Country, with northerly flow persisting in
the wake of the front. However, despite the presence of this weak
CAA strong adiabatic heating is ongoing with temperatures ranging
from the upper 80s to upper 90s area-wide. West Texas Mesonet data
shows a reservoir of dewpoints near 60 degrees with the highest
dewpoints across the extreme southern Texas Panhandle and eastern
Rolling Plains. The WTM data and visible satellite imagery indicates
a well mixed boundary layer, evident by the suppression of any CU
across the CWA at this time; and this is also captured by recent RAP
soundings.
Isolated to perhaps widely scattered thunderstorms will be possible
this evening across portions of the South Plains this evening where
weak, isentropic ascent exists near the front beneath the mid/upper
level ridge. Dense CU development is ongoing across the Big Country
and extends southwestward into the Permian Basin, with additional CU
development translating westward into the CWA. While the airmass
will be uncapped this afternoon, the caveat will be mid level
subsidence along the eastern periphery of the upper level ridge
which will suppress the overall coverage of convection. Overnight,
weather is expected to be quiet with a secondary frontal surge
across the CWA as a surface high expands southward, and this will be
reinforced by a MCV propagating eastward across southwestern Kansas.
Therefore, temperatures tonight will be similar to the previous
night, ranging from the middle 60s to upper 70s from northwest to
southeast across the CWA, respectively.
The exit region of the 250 mb jet streak analyzed on the 12Z upper
air map is forecast to nose into the TX Panhandle tomorrow
afternoon. The arrival of this feature will result in an increase in
high level difluence atop veered/northerly 500 mb flow as the mid/
upper level high centers over the Four Corners region. Slight
amplification of the steering flow will occur, and the CAA from the
northerly flow aloft and the weak geopotential height falls will
result in an increase in the depth of the elevated mixed layer.
Forecast soundings indicate MLCAPE increasing to around 1500 J/kg by
the mid afternoon hours across the South Plains. This, combined with
a weakly capped air mass and meager shear, should result in the
development of isolated to scattered thunderstorms across the
aforementioned area tomorrow afternoon. The primary storm mode is
expected to be multi cells particularly in the form of clusters to
perhaps broken lines given the slight increase of steering flow with
storms propagating to the southeast. While the boundary layer will
not be as deeply mixed as today, the dry sub-cloud layer will still
facilitate the potential for strong downbursts, and with the water
loading of updrafts, a severe caliber wind gust cannot be ruled out.
Chances for thunderstorms will continue to increase into the evening
and morning hours. Please read the discussion below for more
details.
&&
.LONG TERM...
(Sunday night through next Friday)
Issued at 255 PM CDT Sat Aug 26 2023
By tomorrow night, the upper ridge will be centered over Arizona
with very weak northerly flow aloft. A developing shortwave paired
with monsoonal moisture on the eastern extent of the ridge, along
the Rockies, will give way to precipitation across the area tomorrow
evening into Monday. The best timing of deep moisture will be
tomorrow evening into Monday morning with PWATs around 1.5" to 2". A
few storms may become strong with wind gusts up to 60 mph early
tomorrow evening due to limited instability before temperatures cool
at the surface with the loss of daytime heating. The main threat
thereafter will be periods of heavy rainfall, especially across the
South Plains where confidence is higher in deep moisture profiles.
Heading into Monday morning, confidence drops in how long the
precipitation continues through the day. Some model guidance brings
dry air into the atmospheric column earlier, while other models hold
onto the deep moisture through the afternoon and early evening hours
across the western South Plains. Given the variability in solutions,
the NBM chance PoPs were maintained across the aforementioned area.
By Monday night into Tuesday, dry air will overtake and any
precipitation chances will begin to diminish for the forecast area.
Continuing into the end of the work week and into the weekend, the
upper ridge will start to move eastward again towards the northern
portions of the Southern Plains region.
The temperatures forecast for Monday may be a bit tricky with the
potential for precipitation and extensive cloud cover through the
day. The NBM was maintained for now with highs in the 80s across the
Caprock and lower 90s off the Caprock. There is a potential that
temperatures, especially along the Caprock, may not even warm out of
the 70s. Tuesday also remains a bit tricky with temperatures, so the
NBM was also maintained for now as the trend of the blend is going
slightly warmer than the previous forecast. Confidence is too low to
warm temperatures any further with the lingering uncertainty.
Outside of the Monday and Tuesday, temperatures will begin trending
towards above normal with highs in the upper 90s to lower triple
digits by the weekend.
&&
.AVIATION...
(00Z TAFS)
Issued at 624 PM CDT Sat Aug 26 2023
VFR conditions are expected through the TAF period. Isolated
thunderstorm activity will likely remain to the east of PVW and
LBB and to the south of CDS this evening. There is a low chance of
rain and thunderstorms tomorrow morning at PVW and LBB but have
not included in TAF due to low confidence. Thunderstorm chances
will begin to increase tomorrow afternoon and evening towards the
end of this TAF period.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...12
LONG TERM....11
AVIATION...17
Area Forecast Discussion
National Weather Service Medford OR
856 PM PDT Sat Aug 26 2023
.DISCUSSION...A small update was made to add the new/latter
portion of the 18Z HRRR smoke forecast, extending into Monday
evening. The previous discussion from this afternoon is still
valid, with a general continuation or slight worsening of the
smoke in our area likely into Thursday.
Conditions on Sunday and Monday will still have quite a bit
of resemblance to those of today and yesterday as our region
remains between two broad features, a trough far offshore and a
ridge over the Desert Southwest. The trough will push inland
Monday night into Tuesday. This will bring a thicker, longer
lasting marine layer of low clouds to the coastal counties (and
extend to around Roseburg early Tuesday morning), cooler
temperatures across the area, and gusty westerly winds east of the
Cascades on Tuesday afternoon. It may also bring a few showers,
with a slight chance probability Coos, Douglas, and possibly also
northern portions of Klamath and Lake counties.
The marine layer will thicken Tuesday night and may fill the
Umpqua Valley by early Wednesday morning, but is not expected to
deepen enough to make it over the Umpqua Divide into Josephine and
Jackson counties...it is still summer. Wednesday looks to be
relatively typical/normal for late August with our area between
exiting and approaching troughs.
Low pressure moving into the region from the Gulf of Alaska is
likely to be the main driver of our weather from Thursday into
next weekend. But, determining the track of broad closed lows
tends to be difficult in the long term, and this is certainly one
of those times. As such, temperatures are likely to be at least
slightly below normal, shower chances are possible for at least
portions of our area, and thunderstorms may be embedded.
&&
.PREV DISCUSSION... /Issued 443 PM PDT Sat Aug 26 2023/
DISCUSSION...Smoke will remain the dominant feature of our
weather, at least into Thursday, with increasing coverage. Coos,
and Modoc counties look to end up with the lowest concentrations.
Thunderstorm activity during the same period of time will be very
low. In the near term, a few thunderstorms may pop up over far
eastern Lake County this evening. Instability is expected over the
northern portion of the southern Oregon Cascades on Sunday
evening, but clouds will be few due to a lack of moisture. There
is less certainty for Monday. The NBM is holding on to a slight
chance of thunderstorms Monday afternoon from the Crater Lake area
northeastward. But, the GFS is among the models forecasting a
continued dry mid-level of the atmosphere, while a couple of the
high resolution models indicate a 5-15% probability farther west,
in eastern Douglas County.
A cold front will pass over the area Monday as an offshore low
finally begins to move east, then the trough itself will pass
overhead on Tuesday. This will lead to gusty, breezy to windy
westerly winds Monday and Tuesday afternoons, with noticeably
cooler temperatures Tuesday into Thursday, including highs
dropping to below normal by a few to several degrees.
The NBM continues to produce high precipitation chances Tuesday
with the passage of the trough, but the GFS and ECMWF, along with
their respective suites, show very little to no chance for
measurable rain. A dry front and trough would certainly be
expected in August, so have kept the forecast a much drier one.
We are keeping light rain possible along the coast and into the
upper Umpqua Basin, typically wetter spots where onshore and
upslope flow may squeeze a hundredth or two of moisture out of
the atmosphere.
The pattern looks to change Thursday with a new trough moving
southeast out of the Gulf of Alaska, then digging south into
Oregon. There are wide variety of model solutions regarding the
track of the trough later Thursday through the the end of the
week, from the center tracking anywhere between areas offshore
and areas east of the Cascades Friday, then taking up positions
overhead or to the south on Saturday. Where it tracks will make a
big difference in expected conditions, and the models show no
clear preferred solution. The forecast continues to reflect a
mean of the model suites, but expect this to change as the models
hone in on a solution over the next several forecast cycles.
AVIATION...27/00Z TAFs...Area wildfires are producing widespread
smoke and haze with visibility restrictions for many areas west of
the Cascades. This will continue to be the case at Medford and
Roseburg airports, which could see periods of MVFR and IFR
visibility through the TAF period. Tonight, the smoke will spread to
the Cascades and eventually over into the Klamath Basin east of the
Cascades. This could create brief MVFR visibilities for the Klamath
Falls airport into Sunday morning, but timing is uncertain.
At the coast, widespread IFR/LIFR is impacting areas from near
Nesika Beach southward. Farther north, an area of clear sky and VFR
exists from Port Orford up around Cape Blanco to near Bandon. The
marine stratus briefly became scattered at North Bend earlier, but
has since gone back to MVFR. We expect most areas will fill back in
this evening with stratus and fog and IFR/LIFR conditions overnight
into Sunday morning for near all of the coast and offshore waters.
These should break up again Sunday afternoon. -Spilde
MARINE...Updated 200 PM PDT...A weak pressure gradient will
lead to weak winds and relatively calm seas through early next week.
A thermal trough will develop by the middle of next week along the
south coast of Oregon. This will result in increasing north winds
and steep wind driven seas late Wednesday afternoon. Moderate to
strong north winds are expected to persist into Thursday. -Schaaf
/Guerrero
FIRE WEATHER...Updated 200 PM PDT Saturday, August 26, 2023...The
latest satellite image shows marine stratus along most of the
coast and into the coastal valleys, which has been slow to burn
off. Elsewhere skies are clear, however we do expect some cumulus
build ups later this afternoon east of the Cascades.
Most of the forecast period will be dry through at least the middle
of next week. The only fly in the ointment will be late this
afternoon into early this evening in northern Fire zone 625 where an
isolated thunderstorm or two is possible (15%).
Smoke is most extensive in Fire zones 616 (western part), the
Illinois Valley and near the fires in northwest California.
An upper level low will remain nearly stationary into the start of
next week, then will get kicked inland Monday night into Tuesday as
an upstream upper trough over the Gulf of Alaska moves east. This
will send a dry cold front into the area Tuesday.
The aforementioned upper low will swing into the area Tuesday and
this has the makings for moderate to strong winds along and east of
the Cascades Tuesday afternoon into early Tuesday evening. 700 mb
winds are not that impressive (15-20kts). However, 600 mb winds are
impressive (25-35 kts) and this is the time of the year when winds
could mix down near the surface from this level. This is a slight
downward trend from yesterday, but it`s still will be a concern. The
pressure gradient will be tight, but the one limiting factor with
Tuesday will be the RH`s. Right now were expecting to see a slight
uptick (slightly higher relative humidities) Tuesday afternoon which
could keep conditions above critical thresholds, but it will be
close. Even if critical thresholds are not met, any existent
holdover or smoldering fires from yesterdays lightning could "wake
up" and become active.
Weak upper troughing remains Wednesday, with dry and stable
conditions.
After Wednesday, the operational models differ with the strength and
arrival of the next upper low on Thursday and Thursday night.
However the the general consensus is for the upper low to move south
and become cutoff from the main flow late next week into next
weekend. This would lead to a cooler and wetter pattern, with
showers and at least isolated afternoon and evening thunderstorms.
-Petrucelli
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...None.
CA...None.
PACIFIC COASTAL WATERS...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
257 PM PDT Sat Aug 26 2023
.SYNOPSIS...
The heat will be on for Sunday and Monday, with temperatures
warming back up into the 90s regionwide. A robust system brings
showers and scattered wet thunderstorms Monday night into Tuesday
night. Rain will continue into Wednesday, and may be heavy at
times across the northern mountains, before a drying trend into
the end of the week. Temperatures drop with the Tuesday system,
sitting below normal through Thursday, before moderation takes
place going into the end of the week.
&&
.DISCUSSION...
Tonight through Monday: While a closed low sits off the WA coast,
a ridge of high pressure remains over the region, giving way to a
warming and drying trend through the weekend. Easterly winds have
ushered in drier air, meanwhile haze and smoke from area fires
lingers.
* Temperatures: Anticipate an additional 4 to 6 degrees of
warming on Sunday with daytime highs in the 90s region wide. A
couple degrees of warming is forecast for Monday, being the peak
of the heat. Overnight lows remain mild in the mid 60s across
the LC Valley, Okanogan, and the Wenatchee area on the mid
Columbia, meanwhile temperatures will dip into the lower 50s in
the northeast WA valleys. Heat risk remains in the moderate
level across the low lands of the Inland NW with a few pockets
of high in central WA.
* Thunderstorms: Storms have been isolated across northern Oregon
and continue to creep northward, reaching the southern Columbia
Basin, Blues and southern ID Panhandle through early evening.
Not much in the way of precipitation is expected, although gusty
outflow winds can be anticipated. For Sunday, the focus shifts
north along the Cascade crest where elevated instability
increases. Already seeing cumulus builds ups this afternoon. By
Sunday, there’s a 10-15% of thunderstorms along the crest of the
northern Cascades. This pattern repeats for Monday afternoon as
well.
...THUNDERSTORMS WITH GUSTY WINDS, HAIL, AND HEAVY RAIN MONDAY
NIGHT INTO TUESDAY...
Monday night through Tuesday: Major pattern change expected as the
low off the WA coast swings inland. This will bring an active
period with thunderstorms, some strong with gusty winds, hail and
heavy downpours Monday night for central WA, and then spreading
into extreme eastern WA and the Idaho Panhandle for Tuesday.
Anticipate dramatic cooling by 8 to 18 degrees on Tuesday and
breezy winds.
* Thunderstorms: The threat increases across the Cascades by
Monday evening and spread into central WA overnight. Instability
remains high through the night with elevated CAPE values near
1000 J/kg seen in the NAM. This has the potential to lead to
strong outflow winds and hail with the thunderstorms. Pwats
steadily increase into Tuesday, increasing the threat for heavy
rain. Thunderstorm chances bump up to 30-40% by Tuesday
afternoon with heavy downpours being an increasing threat,
especially across north-central into northeast WA.
* Winds: Gap winds increase in the lee of the Cascades Monday
evening with gusts of 15 to 25 mph during the overnight hours.
Westerly winds increase and become more widespread across the
Columbia Basin, Palouse, Spokane area, and LC Valley by Tuesday
afternoon with gusts of 25 to 35 mph. These winds are
significant especially for fire weather concerns, although
relative humidities will also be on the increase which will help
lessen fire spread especially with an increase of showers and
thunderstorms.
Tuesday night through Saturday: A moist, cool upper trough will
bring areas of rain and modest thunderstorms chances to the area
through mid-week, before drier weather develops and temperatures
moderate up toward normal. Tuesday evening the negatively-tilted
upper trough will be in the process of lifting through the area,
with modest moisture (PWATS over 1 inch) and instability wrapped
up in it. Rain and a chance of thunderstorms will be found over
much of north and eastern WA and ID. Lower chances will be found
over south-central WA. As the evening progresses into Tuesday
night and Wednesday the higher rain potential shifts toward the
north and eastern mountains, with the overall potential for
thunderstorms likewise declining though not entirely ending. Some
stronger thunderstorms will be possible Tuesday evening, with a
potential for strong winds and hail with the unstable negative-
tilted through lifting through. Locally heavy rain will also be
possible and we will have to monitor for localized/isolated
flooding or debris flows, especially near any burns scars or
steeper terrain. From Tuesday overnight into Wednesday the threat
of strong winds/hail become smaller. However, some potential for
flooding/debris flow impacts from heavier rain remains, with the
focus shifting toward the NE WA and N ID mountain zones. In
general, winds will be around 10-20 mph, with gusts of 20-30 mph
from Tuesday evening through Wednesday, before speeds start to
abate. By Thursday the upper trough starts to split and lose
influence over the region, with a ridge starting to build in
Friday and Saturday. Shower chances will linger near the Canadian
border and Cascade crest Thursday, with drier weather thereafter.
Temperatures will be around 5-10 degrees below normal Wednesday
and Thursday, the warm closer to or slightly above normal toward
the end of the week. /Solveig
&&
.AVIATION...
00Z TAFs: VFR and generally dry conditions will prevail. Some
middle to high clouds will continue to increase from the south,
mostly from the remains of precipitation to the south. Confidence
still supports most of that precipitation falling apart before it
tracks too far north. With that said, isolate -shra/-tsra cannot
be ruled out near the Blue Mountains or Camas Prairie and
portions of the deeper Columbia Basin, some of which could be in
the vcnty of EAT, MWH, LWS and PUW before 06Z. Haze from regional
wildfires will persist, which could provide localized MVFR
conditions; confidence leans away from such impacts around TAF
sites as HRRR smoke guidance does not change concentrations
drastically over the next 24 hours. /Solveig
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 59 91 60 94 60 80 / 0 0 0 0 0 60
Coeur d`Alene 59 92 60 94 61 80 / 0 0 0 0 0 60
Pullman 56 91 57 94 55 74 / 0 0 0 0 0 60
Lewiston 67 99 67 100 66 82 / 0 0 0 0 0 60
Colville 49 92 50 95 52 82 / 0 0 0 0 0 60
Sandpoint 54 89 55 91 57 84 / 0 0 0 0 0 40
Kellogg 61 89 64 92 64 81 / 0 0 0 0 0 60
Moses Lake 60 97 61 98 61 80 / 0 0 0 0 30 80
Wenatchee 67 95 69 98 66 78 / 0 0 0 0 40 70
Omak 61 98 65 100 67 83 / 0 0 0 0 10 70
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Pueblo CO
523 PM MDT Sat Aug 26 2023
.SHORT TERM...(This evening through Sunday)
Issued at 258 PM MDT Sat Aug 26 2023
Key messages:
1) Mainly mountain/high valley showers and thunderstorms this
evening.
2) Slight upturn in storm coverage on Sunday, with an increasing
chance of storms into the I-25 corridor.
Currently, convection finally starting to increase/strengthen over
the high terrain as air mass over the mountains has destabilized
(CAPE 800-1200 J/KG), while I-25 corridor has seen cool/stable
conditions as morning cloud cover has been slow to burn off. For
this evening, expect sct to numerous showers/storms over the
mountains to slowly drift east, with radar trends and various CAMs
suggesting Fremont and Custer counties will see the best coverage of
precip, though all mountains/interior valleys have a chance for at
least a brief storm through sunset. Locally heavy rain will be
possible, as storm motions are fairly slow. Not buying the HRRR
depiction of storms surviving all the way to the I-25 corridor and
beyond given lack of instability east of the mountains, though if
stronger storms do fire in Fremont County, some showers/light rain
may drift make it into Pueblo County and the srn I-25 corridor
before dissipating by late evening. Overnight, backed off pops
somewhat after midnight as most models end showers by 06z-08z,
though some sprinkles likely to persist over the peaks into the
morning given rather moist air mass in place.
On Sunday, another round of afternoon storms is likely over the
mountains/interior valleys as moisture remains in place, with
vertical motion provided by weak upper level speed max rotating
through the area. I-25 corridor should see an increased chance of
convection by late afternoon as well, with southeast surface winds t
many locations holding moisture in place, allowing surface CAPE to
climb to around 1000 J/KG by late day. Least chance of storms will
be over the far eastern plains, where air mass continues to look
fairly stable. Again, locally heavy rainfall the main risk with any
storms (eastern mountain slopes look favored), as steering flow is
weak and 0-6km shear profile is less than 30 kts. Max temps will
climb back into the 80s on the plains with more sun expected, while
mountains bounce back into the 70s.
.LONG TERM...(Sunday night through Saturday)
Issued at 258 PM MDT Sat Aug 26 2023
Key messages:
1) Scattered showers and thunderstorms are expected from Sunday
evening through Monday. Some storms could produce flash flooding.
2) Drier conditions are anticipated Tuesday through Wednesday
with only isolated to scattered afternoon storms over the higher
terrain.
3) Slight uptick in afternoon and evening thunderstorm chances on
Thursday and Friday, with a few storms possible over the plains as
well.
4) Overall temperature trend will be cool and slightly below average
through Tuesday, then a warming trend with temperatures slightly
above average on Thursday and Friday.
Detailed discussion:
Sunday evening through Monday...
An upper level disturbance transitioning through, along with an
abundance of moisture due to the remnants of a tropical system, will
continue to provide widespread coverage of showers and thunderstorms
over most of southeast Colorado Sunday evening through Monday. High
resolution model guidance and CAMs alike continue to show most of
the activity being confined to the higher terrain and along the I-25
corridor, with lesser coverage over the far eastern plains. The
higher probability of storms looks to occur over the central to
southern portion of the I-25 corridor on Sunday evening, although
there could still be some heavier showers over the northern portion
as well, especially around Monument Hill. Given the higher amount of
CAPE and instability, there could also be some heavier storms and
perhaps a rogue storm with severe criteria outflow winds over the
southern Sangre de Cristo Mountains and Raton Mesa area. Some
storms could prove to be problematic in terms of flash flooding
for the burn scar areas and perhaps the urbanized areas along the
I-25 corridor if storms are able maintain intensity as they move
off the mountains. The majority of the eastern, and especially the
far eastern plains, will likely remain dry given the more stable
conditions in place. Temperatures will remain cool and dropping
into the upper 50s to low 60s over the plains, and generally in
the 40s to low 50s for high country, with a few locations in the
upper 30s for the highest elevations.
On Monday, the mid to upper level flow behind this disturbance,
along with a broad swath of moisture associated with it will cause
more showers and storms to develop during the afternoon over the
higher terrain and then move over into the adjacent valleys and
plains throughout the day. Again, the coverage on Monday evening
will be very similar to Sunday evening, with most of the heavier
showers and storms being over the southern Sangres and along the
southern I-25 corridor. Given that shear will not be very strong,
there is lesser confidence with storms becoming severe, however the
slower movement could cause concern for flash flooding, especially
over the burn scar areas and perhaps some of the urbanized areas
along the I-25 corridor. Easterly flow at the surface over the
plains could also help with some upslope enhancement with these
storms. Because of this, WPC still has a marginal risk for excessive
rainfall through Monday over most of the higher terrain and I-25
corridor. Temperatures will still be cool and nearly 10 degrees
below the seasonal average for highs on Monday.
Tuesday through Friday...
There will be a drying trend taking place from Tuesday through
Thursday, which is reflective in the decreasing PWAT values in the
ensembles during this time as drier air is advected into the mid to
upper levels behind the exiting U/L disturbance. Storms developing
over the higher terrain during the afternoon hours will be mainly
isolated and there will be very little chance for anything to move
over into the plains. It will still remain cool on Tuesday, although
there will be a gradual warmup as ridging begins to build back in
over the region and south to southwesterly flow returns in the lower
levels, with temperatures return to being above the seasonal average
by Thursday. It will also be very warm on Thursday and Friday,
although ensembles do show a slight uptick in PWAT values and the
deterministic models are also in close agreement with this as there
will be some troughing to the northwest which helps to push the
monsoonal moisture plume further towards the east and over the
region. There will also be a better chance for storms to move out
over the plains with increasing mid-level shear for both of these
days. -Stewey
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 519 PM MDT Sat Aug 26 2023
KALS...showers and thunderstorms will likely impact the terminal
through around 04z this evening. Variable winds with gusts near 35
to 30 kts and reduced CIGS and VIS are possible with any storms
that move over the terminal. Areas of fog are possible overnight,
with VIS falling to 3 SM or less through Sunday morning. Another
round of afternoon showers and thunderstorms are possible tomorrow
afternoon.
KCOS and KPUB...CIGS around 3 to 6 kft will be the main concern
through the overnight hours. Southeasterly winds will likely keep
KCOS socked in overnight. Improving conditions are expected Sunday
morning into the afternoon, with low chances for afternoon
showers and thunderstorms. Mozley
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PETERSEN
LONG TERM...STEWARD
AVIATION...MOZLEY