Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/12/24
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
854 PM CDT Sun Aug 11 2024
.KEY MESSAGES...
- Below average temperatures (5 to 10 degrees) tonight through
Monday night and a 30-75% chance of showers and thunderstorms
across portions of central and northeast South Dakota tonight.
- Additional chances for moisture in the form of thunderstorms run
from late Tuesday through early Thursday. Severe weather potential
exists but with high uncertainty on timing/intensity/coverage of
storms at this time.
&&
.UPDATE...
Issued at 849 PM CDT Sun Aug 11 2024
Showers and thunderstorms really dissipated as the complex moved
into central SD. Made adjustments to PoPs to better account for
radar trends. Any activity the rest of the night appears to be
rather minimal, but will maintain 20-40% chances across the CWA,
eventually trending dry from north to south by morning. Also made
some adjustments to sky conditions to better reflect satellite
trends.
&&
.SHORT TERM /THIS EVENING THROUGH MONDAY NIGHT/...
Issued at 213 PM CDT Sun Aug 11 2024
At 2 PM CDT, skies are partly sunny to mostly cloudy. And, there is
a plume of smoke aloft over the region as well. Showers that moved
into central South Dakota earlier this morning are holding together,
and have begun their descent into southeast South Dakota. Behind
this batch of showers, scattered to numerous showers and
thunderstorms are noted on radar back over far western South Dakota,
moving generally east. A southeast wind of 5 to 15 mph has developed
while temperatures warm through the 70s for the most part.
With a large upper level blocking high to the north and an upper
level low churning over Ontario and Quebec, the upper level steering
flow is a brick wall to the north and east, leaving steering flow
winds to direct shortwave energy southeast across Montana and the
Dakotas through tonight. The previously mentioned (elevated)
convection back to the west appears to be close to being rooted in
the boundary layer as it crosses UNR`s CWA. If it does, there would
be adequate deep layer shear to support organized/strong storms. But
CAPE is somewhat limited today. Low level shear (0-1km and 0-3km) is
low today in this CWA, And, low level CAPE is low, too. But, the
system helping to generate these thunderstorms is riding along on
the coat-tails of a 90-100 knot upper level speed max. So, plenty of
synoptic-scale lift/diffluence support. Increasingly, the radar
shows a line of storms forming out west (a sign of possible severe
straight-line winds in the future?) The latest few runs of the HRRR
suggest this line of storms will build south-southeast through the
UNR CWA, potentially glancing the far southwestern-most forecast
zones with some strong storm potential through ~01Z this evening.
Otherwise, there may be some lingering mid-level WAA-forced showers
tonight over portions of central and northeast South Dakota. Then,
the forecast should basically go to a dry one for the entire CWA
through Monday night as mid-level heights rise and the surface high
just off to the east pushes back a bit and re-asserts influence on
the boundary layer over this CWA. Limited low level WAA through the
period, so perhaps some airmass moderation combined with daytime
heating on Monday could push the needle up into the upper 70s to low
80s across the CWA. Also, worth a mention, the latest HRRR-smoke
model run shows this current smoke plume aloft diminishing some
through Monday morning, before the next ribbon of smoke aloft
advects over this region Monday night.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 213 PM CDT Sun Aug 11 2024
No significant ensemble 500 MB clusters to analyze the in long term
period, which generally leads to high confidence in the overarching
pattern. Upper level ridging Tuesday will gradually give way to
southwest flow as a trough develops over the PAC NW. Several rounds
of shortwave energy are expected ahead of the main trough passage
across the northern plains. The main trough then swings through
somewhere in the Thursday time frame. This is followed by northwest
flow due to a building west coast ridge by the weekend.
Tue/Wed, as the southwest flow pattern takes hold, mid level warm
air advection and moisture will also return. NAEFS/EC climatological
percentiles are exceeding 90% for PWATS and 850 MB specific
humidity. Likewise, NBM surface dewpoint probability of >= 65
degrees exceeds 90% across our western CWA Tuesday afternoon and
then spreads across the rest of the CWA Wednesday afternoon and
lingers into Thursday. Therefore, high confidence in the return of
moisture/instability. This combined with ample bulk shear Tue/Wed
should set the stage for thunderstorms, with the possibility of some
of those being strong/severe storms. Of course, timing of said storm
develop is tough this far out. Generally speaking, the higher POPs
(40-60%) are trending toward Tuesday night into Wednesday and again
Wednesday night into Thursday. Will also have to watch for capping
potential, although at this point it looks low (LREF 700 temps
exceeding 12C is 30% or less during the time period). Depending on
the timing of the main trough passage, which does lack consensus
among models, Thursday may be fair game for thunderstorm
development as well. The upper level northwest flow and cold air
advection pattern then returns for the weekend.
Well a general warming trend is expected through the week,
temperatures will hover near normal, with normal being in the mid
80s west to low 80s east.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 628 PM CDT Sun Aug 11 2024
Terminals KABR,KATY,KPIR,KMBG
Isolated -SHRA have developed this evening across northeast SD,
possibly affecting KABR/KATY and have inserted VC (vicinity)
mention for those sites. Also watching an area of SHRA (possible
TSRA) moving eastward into the KPIR region which will affect them
to start the TAF period. Otherwise, MVFR CIGs are also possible in
KPIR late tonight into Monday morning.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...TMT
SHORT TERM...Dorn
LONG TERM...Serr
AVIATION...TMT
Area Forecast Discussion
National Weather Service Bismarck ND
954 PM CDT Sun Aug 11 2024
.KEY MESSAGES...
- Scattered showers and isolated thunderstorms can be expected
south and west of Lake Sakakawea and the Missouri River late
this afternoon into early this evening.
- Temperatures are expected to warm closer to normal through
this coming week.
- There are medium chances for showers and thunderstorms Tuesday
afternoon through Wednesday. A few storms could be strong to
severe in western North Dakota Tuesday afternoon and evening.
&&
.UPDATE...
Issued at 950 PM CDT Sun Aug 11 2024
Surface low over northeastern South Dakota could dissipate fog
development tomorrow morning. Thunderstorms have ended as a few
showers linger across portions of western and central North
Dakota. Showers should diminish in a few hours. No updates
needed at this time as the forecast remains on track.
UPDATE
Issued at 624 PM CDT Sun Aug 11 2024
Showers and thunderstorms continue across western North Dakota
this afternoon weakening this evening. Visibility reductions
are possible under showers and observations have observed up to
an 1 inch of rain under some of these storms as they are slow
moving. The upper level low is over southwestern North Dakota
with surface high pressure located over northeastern North
Dakota. Therefore, southerly return flow returns into the
region tonight which could lead to patch fog in the southwest
and portions of the south central tomorrow morning. Adjusted
pops to match current conditions, no other updates needed at
this time.
&&
.DISCUSSION...
Issued at 330 PM CDT Sun Aug 11 2024
Currently, surface low pressure was situated over the Central
High Plains with an inverted trough extending north through
western South Dakota and into far southwest ND. High pressure
remains situated over the eastern Dakotas and Minnesota. In the
upper levels a shortwave was tracking from southeast Montana
into western South Dakota. Back to the west an upper level low
was spinning over southern British Columbia and into the
Pacific Northwest. Showers and isolated thunderstorms over
southwest ND this morning have given way to more stratiform
precipitation. An isolated embedded storm is still possible here
this afternoon. As mentioned yesterday, the convection this
afternoon is more along the periphery of the cloud shield, where
more insolation is resulting in better instability. Isolated
thunderstorms are currently situated from around Sidney Montana,
east southeast through McKenzie and Dunn counties, to around
Beulah and southeast to Morton, Grant, Sioux and Emmons
Counties. This activity is within an area of 500-1000 J/KG
MUCape, but little to no shear and meager mid level lapse rates.
The mean winds in this area are light and resulting cell
movement is slow. These storms could produce some very spotty
areas of heavy rain, but given the isolated nature to the
convection, impacts from heavy rain would be very isolated in
nature. There was a report of 1.31 inches of rain near Sidney
MT, so very local heavy amounts are possible.
Expect convection to diminish this evening with decreasing
clouds in the southwest and far south central. Elsewhere clear
to partly cloudy. The HRRR and RAP have each been bouncing back
and forth as to the areal extent of fog over the west and south
central tonight. As the previous shift mentioned, with the
surface high entrenched over eastern ND and possibly expanding
back west a bit tonight, this setup would be favorable for areas
of fog, especially in the southwest with a southeast upslope
surface flow. Will keep the mention of patchy fog but think
enough uncertainty remains to keep it at patchy fog for now and
let the evening/overnight shifts adjust as needed.
Upper level ridging builds over the Northern High Plains on
Monday resulting in mainly dry conditions over the forecast
area and a developing southerly return flow as the surface high
exits eastward towards the Great Lakes. With this upper level
flow orientation, we could also see a return of wildfire smoke
aloft from western U.SS. wildfires, but currently the amount of
low level smoke appears negligible.
In the Tuesday through Thursday timeframe, the upper level
trough over the Pacific Northwest tracks east across the
Northern Rockies and Northern Plains. This will bring a period
of unsettled weather to the forecast area on Tuesday and
Wednesday. SPC continues to advertise a marginal risk (level 1
out of 5) for severe storms over western North Dakota Tuesday
afternoon and evening. Looking at the latest deterministic
models there looks to be even more uncertainty than yesterday
with some guidance indicating a slowing of the approaching upper
trough, which could delay convection in the west Tuesday. This
could also influence convection, or the lack thereof on
Wednesday as well. Looking at the NBM 1D viewer, not much stands
out with the ensemble temperatures with a gradual warming
through the first half of the week, then nearly steady
temperatures. If I were to pick one thing, it would be the
temperature spread over central North Dakota on Wednesday.
Spreads are not terribly large, but overall, high temperatures
are cooler and the spreads are noticeably larger than those
prior to and also beyond Wednesday, into the upcoming weekend.
This would signal that there is quite a bit of uncertainty with
the passing upper trough late Tuesday and Wednesday. The
uncertainty in temperatures over central ND Wednesday will
probably be a factor in the resulting severe weather potential
on Wednesday as well. Overall though the bulk shear is weaker
across western and central ND Wednesday when compared to
Tuesday.
Beyond Wednesday we see upper level ridging developing over the
areas once again with a possible omega blocking pattern setting
up through the weekend. Currently the NBM is advertising daily
low precipitation chances with near seasonable temperatures but
with a favoring for warmer temperatures west and cooler
temperatures east.
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 624 PM CDT Sun Aug 11 2024
Showers and thunderstorms continue across portions of western
and central North Dakota this afternoon and should dissipate
this evening. Temporary visibility reductions are expected
under showers and thunderstorms. Fog could move into the
southwest and south central tonight into early tomorrow
morning. However, confidence is low if fog will form at KDIK and
KBIS tomorrow morning. Winds will pick up out of the south
tomorrow afternoon leading to breezy conditions.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Johnson
DISCUSSION...TWH
AVIATION...Johnson
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
607 PM CDT Sun Aug 11 2024
...New AVIATION...
.SHORT TERM...
(Tonight through Monday night)
Issued at 133 PM CDT Sun Aug 11 2024
The mid-level ridge swings out into the northern Gulf of Mexico as
surface high pressure anchors into the central Gulf, maintaining
somewhat typical August conditions across Deep South Texas into
Monday night. Tropical moisture increases from the south into
Monday, leading to a better chance of convective development along
the sea breeze, especially on Monday, as well as more streamer
activity along the coast Monday morning. Near normal highs and lows
combined with the increasing moisture elevate Heat Indices each
afternoon to borderline Heat Advisory criteria and keep mornings
muggy with patchy fog near open fields, especially north of the
valley.
&&
.LONG TERM...
(Tuesday through next Sunday)
Issued at 133 PM CDT Sun Aug 11 2024
The long term forecast remains on track. Mid level ridging will
continue over Texas through the period. A weak midlevel trough
will continue to move west across the southern periphery of the
ridge into Tuesday. Tropical moisture associated with this trough
will lead to chances for rain and thunderstorms Tuesday afternoon
with most of this activity remaining confined to areas east of
I-69C. Conditions will dry out for the remainder of the period,
though a few sea breeze showers or thunderstorms can not be ruled
out each afternoon.
Temperatures will remain warm with highs in the upper 90s to low
100s. With more humidity across the region through the week, heat
indices in excess of 105 are expected each afternoon. Heat
Advisories may be possible throughout the week.
&&
.AVIATION...
(00Z TAFS)
Issued at 605 PM CDT Sun Aug 11 2024
VFR is expected at the aerodromes through the next 24 hours. A
TEMPO has been included in the TAFs based on convective signals
indicated by the HRRR model data.
&&
.MARINE...
Issued at 133 PM CDT Sun Aug 11 2024
Now through Monday Night...High pressure across the Gulf of Mexico
maintains generally light southeasterly flow through Monday night,
gradually building seas to 2-3 feet. The chance of showers and
thunderstorms continues offshore, especially during late night and
early morning hours.
Tuesday through Saturday...Generally favorable conditions will
continue on the Laguna Madre and Gulf waters through the period.
Southeasterly winds will remain light with seas of 2 to 3 feet.
Streamer showers and/or isolated thunderstorms will be possible
throughout the period that could lead to locally enhanced winds
and seas.
&&
.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE 80 96 81 96 / 10 30 10 20
HARLINGEN 76 96 77 96 / 10 30 0 20
MCALLEN 80 100 80 101 / 0 20 0 10
RIO GRANDE CITY 78 99 79 101 / 0 10 0 10
SOUTH PADRE ISLAND 82 90 83 91 / 10 10 0 10
BAYVIEW/PORT ISABEL 79 93 79 93 / 10 20 0 10
&&
.BRO WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Area Forecast Discussion
National Weather Service State College PA
938 PM EDT Sun Aug 11 2024
.SYNOPSIS...
Generally dry conditions with comfortable humidity are in store
for much of the upcoming week. with below normal temperatures
early on, then a gradual moderation for the second half of the
week.
Cooler air aloft at the southern edge of an upper level
trough will bring some clouds and the chance for a few showers
and isolated thunderstorms across the Northwest Mountains
tonight through Tuesday.
The next chance for more widespread showers and thunderstorms
returns toward the end of the week as a warm front lifts
northeast from the Ohio Valley.
&&
.NEAR TERM /UNTIL 8 AM MONDAY MORNING/...
Mainly clear skies covered the bulk of the CWA this evening,
with just some highly isolated showers across the northern tier
of the state as an upper level trough swings across the area,
and Lake Erie adds some low level moisture.
Low temps tonight will vary from near 50F throughout the
perennial cold spots of the Northern Mountains and Laurel
Highlands to around 60F in the larger metro areas in the Lower
Susq Region.
&&
.SHORT TERM /8 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
Another round of showers and isolated storms will be possible
Monday afternoon across the far north. Temperatures will be
similar to Sunday, averaging a few degrees cooler than normal.
Looks like Tuesday will be mainly dry. Some weakness in the
upper level flow, something to watch.
Temperatures on Tuesday will be similar to Monday.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Ensembles indicate that upper troughing will begin to weaken and
upper level ridging will attempt to move in for the first part
of the extended period. High pressure at the surface will keep
the region dry through early Friday. As the high shifts off to
the east, southerly flow will develop which will usher in higher
dewpoints and slightly warmer temperatures. Highs Thursday and
Friday will be in the upper 70s and low to mid 80s.
The next chance for rain will come towards the end of the week
as a surface low tracking through the Ohio Valley sweeps a warm
front across Central PA from southwest to northeast.
Considerable differences remain between ensemble members with
respect to the positioning and timing of this system so have
undercut NBM POPs for Friday and Saturday.
All guidance shows an upper low sitting over the area into the
beginning of next week, which will keep temperatures on the
cooler side and will allow for daily rain chances.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
There is high (> 90%) confidence in VFR conditions at all
airfields outside of BFD through 00Z Tuesday. GLAMP and RAP
model soundings continue to suggest low-level moisture will
allow for low ceilings (low-end MVFR to high-end IFR) to
develop at BFD towards sunrise, with the timeframe of highest
concern 11-13Z Monday. There are some signals of these ceilings
developing closer to the 08-10Z timeframe, but confidence
remains too low (20-30%) for mention in the 00Z TAF cycle.
Low clouds are expected to quickly dissipate after sunrise,
giving way to VFR conditions. A few showers are expected to develop
Monday PM across N/NE PA with less confidence on coverage and
location, thus have kept mentions out of the 00Z TAF cycle at
BFD/IPT although those are the two most likely airfields to
experience SHRA impacts after 20Z Monday.
Outlook...
Tue...Scattered PM SHRA/TSRA across N PA.
Wed-Thu...VFR/no sig wx.
Fri...Afternoon SHRA/TSRA.
&&
.CLIMATE...
Heavy rain from the remnants of Debby caused record rainfall at
the following locations:
3.30 inches of rain at Williamsport breaks the old record of
2.90 set in 1917.
3.43 inches of rain at Johnstown breaks the old record of 2.07
set in 2007.
2.64 inches of rain at Altoona breaks the old record of 1.05 set
in 2007.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Lambert/Martin
NEAR TERM...Lambert/Martin
SHORT TERM...Martin
LONG TERM...Bauco
AVIATION...Bauco/NPB
CLIMATE...Colbert
Forecast Discussion at weather.gov/mqt.
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
MARINE...None.
&&
$$
DISCUSSION...Huyck
AVIATION...JDS
MARINE...Huyck
Area Forecast Discussion
National Weather Service Fort Worth TX
654 PM CDT Sun Aug 11 2024
...New Aviation, Short Term...
.SHORT TERM... /NEW/
Update:
An outflow boundary from Oklahoma convection earlier in the day
remained inactive despite a couple of meager updraft attempts
during peak heating. A quiet overnight period is expected with
lows falling into the upper 70s, although urban areas may hold
near 80. Additional convection is likely to occur north of the Red
River overnight into tomorrow morning, but it is rather unlikely
any leftover shower or thunderstorm activity would spread
southward into North Texas, thus no PoPs will be carried through
the short term period. Subsequent forecast issuances will evaluate
whether a Heat Advisory will be necessary to begin the workweek.
-Stalley
Previous Discussion:
/This Afternoon through Monday Night/
A complex of showers and thunderstorms continues to move across
Oklahoma at this hour with the southern fringes now spreading
across the Red River into parts of our northeastern counties.
Despite a fairly strong instability axis farther south and west,
weakening low level inflow into this activity should limit the
overall southward extent and we`ll keep PoPs confined to our far
northern counties through mid afternoon. Late this afternoon,
we`ll have to watch for at least isolated thunderstorm development
across our far western counties where the aforementioned
instability axis will be in place. A tightening theta-e gradient
will develop in the wake of the complex to the northeast and
should result in a zone of low level convergence this afternoon
across the western half of the CWA. This is already reflected in
the latest RAP objective analysis, although no notable cumulus
have developed as of yet. Steepening mid level lapse rates through
the afternoon and a persistent, yet weak band of low level warm
advection could be sufficient for an isolated storm to develop.
Any storm that may develop could produce strong downburst winds,
although we`ll maintain PoPs less than 20% at this time given a
lack of more appreciable forcing. Any convection that develops
would quickly diminish this evening with a mostly clear night
expected and low temperatures in the upper 70s.
Another hot day is expected on Monday with high temperatures near
100 and heat indices approaching 105 degrees. The mid level ridge
will expand a bit through the day and should keep precipitation
chances near zero. While a few spots could reach heat advisory
criteria, we`ll hold off on any issuance at this time given more
humid conditions are expected to arrive later this week.
Dunn
&&
.LONG TERM... /Issued 306 PM CDT Sun Aug 11 2024/
/Tuesday Through Next Weekend/
Grueling summer heat will be back in full swing this week as the
upper level ridge strengthens overhead once again. High
temperatures will top out in the triple digits for most locations
each day, with the hottest temperatures expected Thursday through
next weekend. The main caveat to this will be whether rain chances
will return late in the week as there are some indications of a
weakening in the ridge. However, even if this weakening occurs,
there is good agreement among ensemble guidance that the ridge
will strengthen again next weekend. Heat headlines will likely be
needed for much of the upcoming week as heat index values will
reach between 105-110 degrees for many areas on a daily basis.
Warm nights will continue to offer little relief from the heat, so
ensure you take all measures to protect yourself from heat-
related illnesses throughout the week.
Barnes
&&
.AVIATION... /NEW/
/00z TAFs/
VFR will prevail with southeast surface winds near 10 kts and
occasional gusts up to 20 kts. Daytime cumulus at 5-6 kft and some
passing cirrus will be the extent of cloud cover through the
period.
-Stalley
&&
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 80 100 79 100 81 / 0 0 0 0 0
Waco 76 99 77 99 78 / 0 0 0 0 0
Paris 74 97 76 99 78 / 5 10 0 0 0
Denton 78 100 78 101 79 / 5 5 0 0 0
McKinney 78 100 79 100 79 / 5 5 0 0 0
Dallas 80 101 79 102 82 / 0 0 0 0 0
Terrell 76 98 77 99 78 / 0 0 0 0 0
Corsicana 78 99 79 100 79 / 0 5 0 0 0
Temple 76 99 76 99 76 / 0 5 0 0 0
Mineral Wells 77 102 76 101 77 / 5 0 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Hastings NE
639 PM CDT Sun Aug 11 2024
.KEY MESSAGES...
- Scattered showers and thunderstorms expected tonight, with a
small chance for a strong to marginally severe storm west of a
line extending from Cambridge to Ord.
- Patchy fog expected Monday morning, with at least partial
sunshine returning Monday afternoon.
- Off and on thunderstorm chances (20-50%) expected through the
end of the week with thunderstorm chances diminishing next
weekend.
- Below normal temperatures (70s to low 80s) will continue
through Tuesday, with near to above normal temperatures (mid
to upper 80s) then expected Wednesday through next Sunday.
&&
.DISCUSSION...
Issued at 305 PM CDT Sun Aug 11 2024
Another cloudy and seasonably cool afternoon across the local
area with this mornings showers activity across north central
Kansas having exited the local area. To our west/northwest,
additional showers and thunderstorms are forming across portions
of northeastern Colorado into the Black Hills of South Dakota,
which are expected to track east towards the local area this
evening, diminishing in intensity as they reach the far western
portions of the area where the available instability drops off
significantly. Evenso, could see a few storms hold together,
resulting in an isolated strong to marginally severe
thunderstorm reaching as far east as a line extending from
Cambridge to Ord, but widespread severe weather is not
expected. This is largely unchanged from the previous forecast
and continued to advertise the small potential for an isolated
storm producing quarter sized hail and/or a 60 mph wind gust.
As the responsible disturbance tracks east of the area by
daybreak Monday, models are indicating the potential for some
fog formation across our area, with SREF probs for visibilities
below 3 miles near 50 percent and the HRRR indicating more dense
fog to our west. Given this, expanded in time and coverage fog
potential for Monday morning, although this fog should be
relatively short lived, with partial to mostly sunny skies
expected by midday. With the lessened cloud cover, temperatures
should also increase from the last couple of days, with many
areas topping out of the upper 70s to lower 80s. This will help
to increase instability across the area, as yet another upper
level disturbance is expected to impact the local area during
the evening through overnight hours Monday. This disturbance is
expected to be focused west/southwest of the tri-cities,
although there will be the chance for primarily a non-severe
thunderstorm across nearly the entire area as it tracks by.
With the upper level flow pattern remaining fairly progressive
and active through the remainder of the week, continued off an
on chances for showers and thunderstorms are anticipated, with
the finer details of these disturbances needing to be more
closely refined as the time approaches. The good news is that
most areas should see some measurable precip over the course of
the week, although overall QPF amounts will likely vary
significantly with the 7day QPF from WPC indicating parts of the
area may only receive a quarter of an inch or less of total
precip when all is said and done. Late in the week, the upper
level ridge across the intermountain west is expected to amplify
and transition east across the local area, eventually
diminishing precipitation chances by next weekend as
temperatures return to near or above normal levels.
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 637 PM CDT Sun Aug 11 2024
For KGRI/KEAR Airports:
A few showers and thunderstorms will be possible this evening in
the vicinity of the terminals. Expect IFR to MVFR conditions
through at least midnight. There is the potential for some fog
development tonight into around sunrise. Fog and low
ceilings/visibilities are expected through mid-morning, where
it should begin to dissipate. Ceilings improve to MVFR Monday
morning. Light and variable winds are expected for much of the
period.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&
$$
DISCUSSION...Rossi
AVIATION...Wekesser
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1005 PM EDT Sun Aug 11 2024
.SYNOPSIS...
A stalled frontal zone will lead to isolated to scattered
thunderstorms this afternoon into the late evening. High pressure
builds in throughout the workweek with thunderstorms possible each
day. High temperatures be on a cooling trend starting today and will
continue cooler than normal into the weekend.
&&
.NEAR TERM /THROUGH MONDAY/...
As of 1000 PM EDT Sunday: Convection still bubbling up across the
Upper Savannah Valley, but otherwise, things have quieted down. Even
the current activity is mainly just showers at this point. The 00z
HRRR still wants to develop more convection across the NC Piedmont
around/after midnight, depicting showers and possibly general
thunderstorms around the Charlotte area thru daybreak. Not sure
what it is keying on, and since the inherited forecast does keep
some chance PoPs into the overnight in those areas, have opted
to keep that in with this update. Certainly, the severe threat
looks to have waned, as we lose daytime heating.
Overnight tonight, it should remain cloudy enough and winds should
stay elevated enough to preclude more than some patchy mountain
valley fog. Temperatures will fall into the low 70s or even upper
60s across the I-40 corridor and the NC Foothills. Tomorrow,
convection once again looks to remain isolated, with virtually
all the hi-res guidance depicting initiation remaining confined
to zones south of I-85.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
As of 1250 PM Sunday...A broad upper trof gives way to a large
scale subs regime during the short range. This will enable more of a
convectively suppressed atmos with warming mid levels and dry dense
column air.
The latest NAM/GFS soundings show a strong cap arnd h7 in place by
Tue evening persisting thru the period, while deep shear increases a
little abv h85. A reinforced Canadian sfc high will dominate at the
surface which will make deep convec hard to come by each afternoon
owning to lowering sfc tds and maxTs. Also, PWAT values go down yet
remain a little abv normal...so storms that do develop will be
capable of producing stg downpours. Otherwise, not expecting much in
the way of stg/svr tstm development each afternoon with the NC mtns
likely receiving the brunt of the activity. The 12Z GFS is a notable
outlier in keeping a sfc trof active east of the mtns each afternoon
and this soln has been given little weight in the fcst process. Will
side with the lower PoP guidance values based on the overall
pattern, which includes a mix of consMOS.
Max temps will reach right arnd normal levels Tue, then drop a
couple degrees below normal Wed in continued n/ly to ne/ly llvl
flow. Mins will hover a little abv normal each morning.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 135 PM Sunday...Broad sfc high pressure remains dominant and
becomes reinforced Thu as a 1021 mb center develops across the srn
Glakes and builds down the east coast. This high will be supported
by a stg subs pattern aloft which will inhibit convec chances Thu
outside of upslope -shra/tstms instigated by moist e/ly flow within
the BL. The upper ridge begins to shift east early Fri and energy
rounding the axis may bring a nocturnal MCS to the NC mtns by
daybreak. Too far out for much detail in this scenario, but it may
be one to keep an eye on.
A transition occurs thru the rest of the ext range with a stg ulvl
trof pushing south out of Canada across the Midwest. The op models
as usual this far out have various timing and strength solns with
the GFS the most aggressive with an approaching cold front. However,
all models have the cold front activated and there looks to be good
shear and decent instability as it crosses into the area late Fri
evening or perhaps Sat morning per the more conservative GEM. In any
case, Sat daytime looks to be a convectively active day as the front
slows due to upstream occlusion. Thus, will keep abv normal PoPs
mentioned during this timeframe. Max temps will remain a little
below normal as a weak cP airmass mix continues, while mins remain
right arnd seasonal levels.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
At KCLT and elsewhere: Widely scattered convection is still in place
across the Upstate along a weak frontal boundary settling across the
southern tier of the terminal forecast area. The NC terminals still
look to remain suppressed through the TAF period, while the Upstate
terminals all have VCSH/VCTS this evening. VCSH was introduced at
KCLT after midnight, when some hi-res guidance depicts lingering
showers drifting across the I-77 corridor. The latest statistical
guidance is a little more aggressive than earlier forecasts with
mountain valley fog overnight, so MVFR visibility restrictions
were introduced to the KAVL TAF for a few hours. Another round
of isolated convection is possible tomorrow, but coverage looks
too low to make it into any of the current TAFs.
Outlook: Expect generally isolated to scattered diurnal convection
across the region each day through the middle of the week. Patchy
fog and low stratus will be possible each night in the mountain
valleys and in locations that receive rainfall.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
SYNOPSIS...SBK
NEAR TERM...ARK/MPR
SHORT TERM...SBK
LONG TERM...SBK
AVIATION...MPR
Area Forecast Discussion
National Weather Service Gray ME
1055 PM EDT Sun Aug 11 2024
.SYNOPSIS...
Relatively quiet weather expected into next week as the region
resides between systems. Scattered showers, and possibly some
isolated thunderstorms, are expected tonight through Monday, as
low pressure passes through northern New England. Surface high
pressure nears the region by mid-week.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
1055 PM Update...
Have raised pops once again across much of the forecast area
with precipitation continuing to cross the region as of 0245Z.
The latest HRRR or NamNest has not picked up on the areal
coverage of the showers this evening.
Otherwise, just minor adjustments to the near term portion of
the forecast for the overnight hours. There is still a chance
for thunder over the next couple of hours, but this chance
diminishes with time overnight. Wind gusts to 25 kt remain
possible in a few of the showers late this evening.
Update...
Showers and isolated thunderstorms continue to track east per
latest radar imagery early this evening. The latest HRRR
continues to weaken this precipitation as it enters the forecast
area. However, some light precipitation will enter northern and
central portions of the forecast area tonight. Have upped pops
slightly to mention a possible shower over central areas as well
as the northern sections.
Otherwise, only minor modifications have been made to the
overnight forecast package.
Prev Disc...
Impacts:
* No significant weather impacts expected.
Showers are on Northern New Hampshire`s doorstep at this hour
as a shortwave trough beings its approach. This area along with
the western Maine mountains will have the best chance to see
showers and even an isolated thunderstorm through this evening.
There is a chance for showers to drift through central New
Hampshire and Maine as well overnight, as an upper low moves
closer to our area, however this is less certain as the better
forcing remains to the north. Cloudier skies will keep
temperatures a few degrees warmer than last night but
temperatures south of the mountains will still be in the upper
50s to around 60, with lower 50s to the north.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY/...
Impacts:
* No significant weather impacts expected.
Upper low moves overhead tomorrow which will bring a better
chance for showers areawide, however they look to be widely
scattered. The aim for the PoPs forecast was to convey that the
highest chance for showers, and maybe a rumble thunder, will be
in and around the mountains with decreasing chances heading
toward the coast. Otherwise, skies start mostly clear in the
morning south of the mountains, becoming partly cloudy as the
day goes on. High temperatures top out in the mid- to upper 70s
south of the mountains, with low 70s to the north. Skies will
clear overnight as the upper low departs which will allow
temperatures to fall into the mid- to upper 50s south of the
mountains, and low 50s to the north.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Overview: The region will be void of any major weather systems
for much of the week. This brings mainly quiet conditions, with
some days producing afternoon showers. Temperatures will remain
around normal for this time of August.
Details: Conditions abate into Tuesday as low pressure pushes
northeast of Maine. Upper troughing remains as surface ridging
builds into the eastern CONUS. These two conditions persist for
much of the week, resulting in fairly persistent diurnal cycles.
Tuesday will feature building cloudiness and the chance for
sprinkles or showers towards the mountains in the afternoon.
Limited instability and drying mid/low levels brings reason that
any showers should be light and sparse.
Daytime clouds begin to thin in the evening, with mostly clear
skies overnight. Did go a bit lower in min temps, particularly
in valleys, given the clearing skies and winds. Winds wont be
optimal for radiational cooling, but these lower areas should
cool and perhaps fog pretty easily. Wednesday looks very similar
to Tuesday, but with a bit more mid level moisture. This could
support more shower coverage during the afternoon given a bit
better instability. Because of the slow evolution of airmasses
in the region, guidance has a similar theme playing out into
late week for Thursday as well.
Broad spread in the extended amid guidance, but the next chance
for widespread rainfall does not look likely until late this
weekend or early next week.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
Short Term...VFR prevails with the potential for some brief
localized MVFR as showers move through the area tonight and
Monday. IFR possible with valley fog each night. Isolated
thunderstorms are possible as well. Winds remain light through
Monday night.
Long Term...Mainly VFR. Daily afternoon showers are possible for
much of this week, but coverage should remain sparse. Clouds may
tend to spread during the afternoon Wed and Thurs, this could
prompt a few spots of MVFR. Clear skies at night may promote
valley fog development, impacting some terminals such as HIE and
LEB.
&&
.MARINE...
Short Term...Conditions remain below SCA conditions trough
Monday night. Southerly winds gusting 15-20 kts will continue
tonight, shifting westerly toward daybreak Monday. Generally
westerly flow will then continue through Monday night with
lighter gusts, 10-15 kts.
Long Term...Below SCA conditions expected. High pressure at the
surface will track east through the week, approaching the coast.
Otherwise, low pressure aloft will keep some instability over
the area for some daytime showers over land.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.
&&
$$
Cannon/Cornwell
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
950 PM EDT Sun Aug 11 2024
.SYNOPSIS...
A cold front will stall across the region early this week
continuing to bring periods of heavy rainfall and the threat of
flash flooding as the soils are already saturated. High pressure
will build into the area for the middle of next week.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
As of 950 PM Sun...Activity continues to slowly diminish
tonight, although cold front has made some progress southward -
despite weak flow, front is likely draped from Oregon Inlet to
around the Bay River and areas west. As the front continues to
slowly sag southward, off-and-on showers and thunderstorms will
likely persist through the night. The HRRR and other reliable
CAMs are once again suggesting a risk along the Crystal Coast
after 2-3 am. Temperatures will remain warm and muggy with lows
in the mid to upper 70s.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
As of 3 PM Sun...The cold front will be stalled across the
southern coast tomorrow, with yet another active day on tap.
Widespread areas of showers and thunderstorms will develop
through the day with the exception of the far northern reaches
of the forecast area where drier air behind the front will
limit precip coverage. Heavy rain will be the main threat as the
high PWAT air remains over most of the area, and flash flooding
will be possible due to the exceptionally high rain rates.
Temperatures will continue to be below normal with highs in the
mid to upper 80s.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
As of 3 PM Sunday...Cold front will become stalled just off the
coast by early Tuesday. This will bring continued shower and
thunderstorm chances across the area through Wednesday until it
moves further away from the coast. The main concern with this
pattern is the possibility for a few downpours over already
saturated soils, which could lead to additional flooding issues.
WPC has ENC within a marginal risk Monday and Tuesday.
PoPs stick around but will decrease slightly as we progress towards
late-week and high pressure sinks south. Upper troughing, the
lingering front just offshore, and the seabreeze will provide
multiple sources of lift. These showers and thunderstorms, although
some downpours are still possible, shouldn`t be nearly as efficient
as the ones we`ve had over the past week. This slightly drier air
mass with dew points in the 60s will be a welcomed change after
multiple days of torrential rain from Debby`s tropical moisture.
Interaction with this front will also keep our temps a few degrees
cooler than climo with highs in the low 80s across much of the area.
The upper trough begins to depart late week as upper riding takes
over but the seabreeze will keep climo PoPs in the forecast through
the rest of the period. The next frontal system will approach the
area over the weekend as a low across the Great Lakes region moves
eastward.
Focus returns to the Atlantic late week. Guidance is depicting what
will likely become Ernesto, but the aforementioned upper trough is
forecast to keep this system away from the east coast. Regardless of
track, however, impacts in the way of heightened rip current risks
and dangerous boating and surf conditions are to be expected.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
SHORT TERM /Through 00z Tues/...
As of 740 PM Sun...Mixed bag of observations this evening as
band of precipitation continues to drift inland and weaken along
a frontal boundary roughly draped from KECG to KGWW. Scattered
stratiform rain across the coastal plain will persist for the
next couple hours and rapid changes in flight conditions are
likely for the next couple hours before returning to primarily
VFR.
Tonight, abundant low level moisture and weak flow will
encourage stratus development with conditions quickly falling to
IFR after 06z. Fog will preclude IFR cig development by a couple
of hours, with lowest visibilities across the coastal plain
like the past few nights. IFR conditions are expected to
continue until around mid morning similar to the last couple of
mornings, with conditions improving to MVFR for the rest of the
morning with cloud bases around 2500-3000 ft.
Shower and thunderstorm threat returns tomorrow as front
continues to sag south, although highest concentration of
activity will south of a line from EWN to GWW.
LONG TERM /Monday Night through Friday/...
As of 3 PM Sunday...The pattern remains unsettled, which will
present multiple opportunities for sub-VFR conditions through
the period. Multiple instances of heavy rainfall, gusty winds,
fog, and low status can be expected. Eventually by midweek drier
and cooler conditions will move in and lead to mostly VFR
conditions prevailing.
&&
.MARINE...
SHORT TERM /through Tomorrow/...
As of 3 PM Sun...Outside of convection, which could be
widespread at times, favorable marine conditions will exist
through tomorrow as a weak cold front moves into the area. The
front is currently located along the NOBX and will slowly sag
southward tonight and then stall across the southern coastal
waters tomorrow afternoon. To the north of the front winds will
turn to the NE/N at 5-10 kts, while to the south of the front
winds will remain SW at 5-15 kts. Seas are expected to be 2-3
ft through tomorrow.
LONG TERM /Monday Night through Friday/...
As of 3 PM Sunday...Sub-SCA conditions are expected through the
period. Tuesday through Thursday will have winds out of the NE
around 10-15 kt. Seas remain around 2-3 ft until Thursday
afternoon when some 4 footers start to build across the outer
central waters.
&&
.HYDROLOGY...
As of 3 PM Sunday...Scattered to numerous showers and storms
expected again this afternoon. With already saturated soils from
4-10" if rain already this week and efficient rainfall rates,
flash flooding will continue to be a concern this afternoon and
have issued a flood watch from noon to 10 PM for all but
Hatteras Island and Ocracoke as most storms are expected to be
over the mainland.
River flooding will continue across many river basins including
the NE Cape Fear, Trent, Neuse, New and Tar Rivers as well as
several tributaries to the rivers through the weekend and into
next week with abundant rain falling will upstream of the FA.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...Flood Watch until 10 PM EDT this evening for NCZ029-044>047-
079>081-090>092-094-193>196-198-199-203.
MARINE...None.
&&
$$
SYNOPSIS...MHX
NEAR TERM...SGK/MS
SHORT TERM...SGK
LONG TERM...OJC
AVIATION...MS/OJC
MARINE...SGK/OJC
HYDROLOGY...MHX
Area Forecast Discussion
National Weather Service Marquette MI
746 PM EDT Sun Aug 11 2024
.KEY MESSAGES...
- Warm and dry weather is expected for the first half of the week.
- Chances for showers and maybe some thunderstorms increase late
next week, but confidence in timing and track is low.
&&
.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 327 PM EDT Sun Aug 11 2024
Water vapor imagery and RAP analysis show an elongating mid-level
low over eastern Ontario and southern Quebec. Hard to discern if
there are any additional shortwaves wrapping around the backside of
this low, but it looks like there could be weak shortwave moving
through the Arrowhead of MN aiding in the formation of diurnal
shower development there. Otherwise over our area, there is an
area of fair weather diurnal cu over the mainly over east half
and southern tier portions of the UP. Temps this afternoon have
ranged from the mid to upper 60s over east half portions under
more persistent clouds to the lower to mid 70s elsewhere.
Tonight, only forecast issue is whether any of the light showers
over the Arrowhead/northern MN could sneak across the lake into the
far western UP this evening. I did put slight chc pops in to account
for this as a few of the CAMs seem to suggest this could be a
possibility. Otherwise, look for min temps tonight mostly in the 50s
under partly cloudy skies. A few upper 40s could be possible over
the eastern interior where max temps have been a bit cooler.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 305 PM EDT Sun Aug 11 2024
Warm and dry weather will prevail for our forecast area Monday
through at least Wednesday thanks to high pressure and mid level
ridging holding fast over the area. Daytime temps each day are
expected to climb into the upper 70s to low 80s and overnight lows
in the 60s by the lakeshores and 50s interior. Winds should be
mostly light with afternoon lake breezes. Skies each day are
expected be partly cloudy to mostly clear, save for diurnal cumulus
development in the afternoon hours.
Toward the end of the week, elongated mid-level trough will push
through central North America. Within this, surface low may develop
ahead of a shortwave pressing through the central US, which then
would gradually spread through the Great Lakes region Friday and
through the weekend. Depending on the speed of this evolution,
shower and thunderstorm activity could begin as early as Thursday,
and then linger into Sunday or Sunday night. There`s a good bit of
uncertainty when it comes to how persistent precip activity will be
and much of this will be dictated by the track of the system.
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 744 PM EDT Sun Aug 11 2024
VFR conditions will prevail for the duration of the TAF period
with no wind impacts.
&&
.MARINE...
Issued at 305 PM EDT Sun Aug 11 2024
Winds of 20kts or less are expected through the first half of the
coming week thanks to high pressure over the region. Toward the end
of the week, a system ejecting out of the Plains will support
surface low development. The low will track into the Great Lakes,
but there`s low confidence in where it will track. If it takes on a
northern route, its possible winds could increase to 20kts or higher
Thursday and into the weekend. This contrasts with the southern
option, which keeps conditions below 20kts. Additionally, depending
on the evolution of the system, some thunderstorm activity may be
possible as early as Wednesday night/Thursday.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Voss
LONG TERM...JTP
AVIATION...TDUD
MARINE...JTP
Area Forecast Discussion
National Weather Service Phoenix AZ
527 PM MST Sun Aug 11 2024
.UPDATE...Updated Aviation Discussion.
&&
.SYNOPSIS...
Ample monsoon moisture over much of the area will continue into
Monday, but shower and storm chances will generally favor higher
terrain areas in Arizona. A significant downtrend in monsoon
activity is likely by the middle of the week across the entire
region as drier air filters into the region. Temperatures through
the upcoming week will average near to slightly above normal.
&&
.DISCUSSION...
Little has changed with the overall synoptic pattern over the past
couple of days with the subtropical high still centered over
Texas stretching into eastern Arizona and the weak upper level
cyclonic circulation positioned over the Baja peninsula.
Additionally, a leftover MCV is currently slowly progressing to
the west northwest across far southern Arizona. This feature has
brought considerable cloudiness for much of the morning and as a
result kept instability lower than forecast while not allowing
the CAP to weaken very quickly. Moisture levels early this
afternoon are still quite high, especially from south-central
Arizona through the Lower CO River Valley with PWATs from 1.5-1.8"
on average and low level mixing ratios around 12 g/kg. The main
forecast question for the rest of today is whether or not the
clearing skies early this afternoon will be enough to spark off
much convection. Current objective analysis still only shows
temperatures mostly in the mid to upper 90s as of 1 PM and it
seems likely we will fall just short of our forecast highs of
105-109 degrees across the lower deserts. The last several runs of
the HRRR show very limited convective development through the
rest of the afternoon, and this may very well be what happens as
the CIN may be too much to recover from due to the morning
cloud cover. The most likely areas of shower and storm
development are likely to be across the higher terrain well east
of Phoenix and across western Maricopa County. Given the lack of
strong instability and relatively low DCAPEs today, the threat for
any stronger storms should be limited.
Heading into Monday, the overall pattern will remain nearly
unchanged as PWATs will continue to remain elevated at 1.5"+ and
additional lobes of vorticity emanating from the Baja low will
remain possible. Thunderstorms will once again materialize during
the afternoon and evening, with the best chances confined across
the higher terrain areas of eastern and southeastern AZ, including
southern Gila County as well as the foothills east of Phoenix.
For the lower deserts of south-central AZ, including Phoenix, any
convective potential will be conditional as to what happens later
today. If later today does not turn out to be convectively active
such that the atmosphere is not overworked, then the chances for
convection across the lower deserts of south-central AZ Monday
evening would increase given that there will be plenty of
instability available as MLCAPE values will likely exceed
1000-1500 J/KG based on the latest forecast soundings.
A significant pattern change is still anticipated by the middle
to latter half of the week as a polar trough traverses from the
Pacific Northwest through the Intermountain West Region. As this
pattern evolves, the flow aloft will be shifting out of the
southwest, which will usher in significantly drier air into the
region. This would likely shut off thunderstorm activity across
the region for a couple of days, mainly Wednesday and Thursday
when ensembles indicate PWATs dropping below 1.2" across the lower
deserts and below one inch across the higher terrain areas. By
Friday into next weekend, as the polar trough moves into the
northeastern CONUS, allowing the subtropical ridge to build over
the southern Plains, a return to south to southeasterly flow is
likely, which will once again cause moisture levels to increase
with storm chances returning.
Temperatures heading into the first of the week will be slightly
cooling down to near normal levels as highs across most of the
lower deserts retreat close to 105 degrees. Then, by mid to late
week as upper-level height fields rise, temperatures will slightly
warm but most likely remain below 110 degrees. Overall, not too
bad of a temperature forecast expected this upcoming week with the
overall HeatRisk expected to be mostly in the moderate category
across most of the region.
&&
.AVIATION...Updated at 0027Z.
South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
The latest satellite/radar trends show quiet conditions across the
Phoenix area with thunderstorms primarily confined to the Arizona
high terrain. Hi-res guidance are supportive of this trend
continuing through the evening with very low confidence in any
convection or outflows reaching the terminals. Thus, do not have any
thunderstorm associated impacts mentioned in the TAFs. Winds will
favor a westerly component through tonight with low confidence in a
typical diurnal easterly switch overnight. A period of light and
variable winds may occur overnight before switching back to the west
once again around 16-17Z Monday. Otherwise, FEW-SCT mid and high
clouds will persist throughout the period.
Southeast California/Southwest Arizona including KIPL and KBLH:
The strong outflow generated by strong thunderstorms across western
Imperial County this afternoon continues to push east of KIPL with
westerly winds expected to continue to weaken going forward.
Westerly winds will continue before switching to the southeast later
this evening. At KBLH, southerly winds will persist through the
period with early evening gusts to 20-25 kts tapering off over the
next several hours. Otherwise, SCT-BKN clouds aoa 7 kft will
gradually scatter out going through the evening at KIPL. FEW-SCT mid
and high clouds will persist at KBLH.
&&
.FIRE WEATHER...
Shower and thunderstorm chances will persist through the next
couple of days, with the highest chances expected across south-
central AZ. With any thunderstorm activity, strong winds with
potential for outflows to travel long distances and cause sudden
wind shifts as well locally heavy rainfall and frequent lightning
can be expected. Storm activity is still expected to trend
downward significantly by the middle of the week as drier air
filters into the region. Aside from the thunderstorm winds, the
overall general winds will continue to follow the typical diurnal
tendencies with some afternoon upslope breeziness. MinRH values
through Monday will remain elevated at between 20-35%, but then
trend slightly downward heading towards midweek with values
ranging between 15-25%. Temperatures during the next several days
will average near to slightly above normal.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
DISCUSSION...Kuhlman/Lojero
AVIATION...Smith
FIRE WEATHER...Lojero/Kuhlman
Area Forecast Discussion
National Weather Service Reno NV
131 PM PDT Sun Aug 11 2024
.SYNOPSIS...
* Increasing winds will provide critical fire weather conditions for
much of the region on Monday.
* Seasonably warm weather will become noticeably cooler by the end
of the week.
&&
.DISCUSSION...
Seasonable warmth, dry weather, and breezy winds are in store today,
brought to you by southwest flow aloft. Wind gusts will increase
this afternoon to 25-30 mph, which will promote a low-end fire
concern as well as choppy lake waters. Latest smoke guidance from
the HRRR indicates that additional smoke from California wildfires
will intrude into western Lassen County and the Sierra Front once
again today.
The synoptic regime today and Monday will feature a shortwave trough
ejecting through northern California into the Great Basin, which
will ultimately provide a 4-8 degree cooldown and gusty winds on
Monday. Winds will be strongest in the afternoon through early
evening with southwest to west winds of 15-20 mph with occasional
gusts of 30-35 mph across lower elevations and sustained winds of 30-
40 mph with 50-60 mph gusts along ridgetops. When coupled with low
daytime humidity, these winds will present several hours of critical
fire weather conditions from the Sierra Front eastward to the Basin
and Range Monday afternoon (see more details in the Fire Weather
discussion below). Furthermore, plan on bumpy flights and choppy
conditions on area lakes on Monday.
The latest suite of ensembles advertise persistent western troughing
for much of next week. This pattern favors dry weather, cooler than
normal temperatures and breezy conditions.
-Salas
&&
.AVIATION...
* Shortwave trough will swing through Monday bringing increased flow
aloft today through early Tuesday. This leads to more turbulence,
mountain waves, and overnight/early morning low level wind shear.
* W/SW surface winds gusting 20-25 knots today will increase to 25-
30 knots Monday mid-day through the afternoon. Typically breezy
airfields such as MMH and RNO have 5-10% chance of gusts over 35
knots today, but a 15-30% chance Monday, per NBM guidance.
* Blowing dust reducing conditions to MVFR is possible Monday
afternoon for areas from HTH-NFL-LOL. Smoke from western Sierra
wildfires is trending more localized due to limited fire activity
thus far today. Not seeing appreciable impacts to east side
airfields through Monday.
-Chris
&&
.FIRE WEATHER...
Increasing southwest to west winds amid low daytime humidities will
yield a 2-4 hour period of elevated to isolated critical fire
weather conditions this afternoon for portions of the Sierra
Front, especially from eastern Lassen County into Washoe County.
This threat will mitigate in the evening as winds diminish in
concert with increasing humidities. Overnight recoveries will
remain poor tonight into Monday morning in western Nevada as
humidity struggles to exceed 40%.
There is high confidence in a greater fire weather concern
materializing Monday afternoon as winds increase in magnitude and
coverage. This will allow for a 4-8 hour period of critical fire
weather conditions from the Sierra Front eastward into the Basin and
Range, warranting an upgrade to a Red Flag Warning for this area. A
potential limiting factor will be increasing mid- to upper level
cloudiness and subsequent lack of sunshine in the afternoon,
although the strength of the winds should compensate. Overnight
recoveries will improve somewhat after today, but will still be poor
for the lower valleys of western Nevada.
-Salas
&&
.REV Watches/Warnings/Advisories...
NV...Red Flag Warning from noon to 8 PM PDT Monday
NVZ420-421-423-429-458.
Lake Wind Advisory from noon to 9 PM PDT Monday NVZ003-004.
CA...Red Flag Warning from noon to 8 PM PDT Monday CAZ278.
Lake Wind Advisory from noon to 9 PM PDT Monday CAZ073.
&&
$$
Area Forecast Discussion
National Weather Service Tulsa OK
931 PM CDT Sun Aug 11 2024
...New SHORT TERM...
.SHORT TERM...
(The rest of tonight)
Issued at 931 PM CDT Sun Aug 11 2024
Scattered showers are starting to develop across portions of
north-central Oklahoma this evening. Showers and thunderstorms
will likely continue to increase in coverage overnight across
northeast Oklahoma as strong 40 knot southwesterly low level jet
develops. PWATs in the 2.00-2.25 inch range will likely support
torrential rainfall in the stronger activity with the potential
for back building/training storms.
Still some uncertainty regarding exactly where the heavy rainfall
axis develops, but latest HRRR runs, including 00Z NAM suggest
highest totals may occur slightly north of where the heavier rain
occurred this morning. Could still see some overlap across portions
of east-central Oklahoma where flash flood guidance remains low.
Regardless, increasing chances for localized, but potentially
significant, flash flooding late tonight into Monday morning
across portions of aforementioned area.
Given the highest rainfall amounts may be confined to a few counties,
opted to not issue a flash flood watch at this time. Did increase
QPF amounts north and east of Tulsa given latest model trends.
Updated forecast out shortly.
&&
.LONG TERM...
(Monday night through Sunday)
Issued at 210 PM CDT Sun Aug 11 2024
Chance PoPs were maintained near the KS and MO borders for Monday
night into Tuesday. Some storms could traverse the periphery of
the expanding mid-level ridge. Forecast high temps climbing into
the upper 90s across much of the forecast area combined with the
humidity will yield solid advisory level heat across much of the
area. By Wednesday, the mid-level ridge will be firmly in control,
and another day of heat headlines are likely. There is still some
uncertainty regarding the evolution of the upper air pattern for
the latter part of the week. Today`s GFS looks like yesterday`s
EC, showing an upper trough sliding across central part of the
country and an associated front pushing thru the region Thursday.
The EC shows a weaker trough to our north and weak boundary
pushing into the northern areas. Again, will stick with the
blended guidance chance PoPs across the north, but will use some
CONSRaw and CONSMOS to shave some degrees off the high temps near
the KS and MO borders in the Thursday and Friday time frame.
Lacy
&&
.AVIATION...
(00Z TAFS)
Issued at 620 PM CDT Sun Aug 11 2024
A mix of MVFR to VFR conditions are found across eastern Oklahoma
and western Arkansas this evening. This trend is set to continue
through tonight and into Monday with showers/storms expected to
impact area sites overnight into Monday morning. IFR conditions
will possible within thunderstorm areas. Conditions begin to improve
Monday afternoon.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 72 91 74 97 / 50 50 10 10
FSM 71 90 74 99 / 20 40 10 20
MLC 74 95 76 98 / 30 30 0 10
BVO 69 91 69 96 / 60 40 20 20
FYV 67 88 70 94 / 40 70 20 30
BYV 66 88 69 91 / 60 80 20 40
MKO 71 90 74 96 / 40 50 10 10
MIO 68 89 70 92 / 70 70 30 40
F10 72 93 74 97 / 40 40 10 10
HHW 73 96 76 99 / 10 10 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...None.
AR...None.
&&
$$
SHORT TERM...12
LONG TERM....30
AVIATION...10