Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/01/24
Area Forecast Discussion
National Weather Service La Crosse WI
1043 PM CDT Sat Aug 31 2024
.KEY MESSAGES...
- Seasonably cool conditions likely through early to mid
portions of the coming week.
- Modest shower/storm chances (20 to 40%) return Thursday, but
overall dry conditions are favored for much of the coming
week.
&&
.DISCUSSION...
Issued at 210 PM CDT Sat Aug 31 2024
GOES visible satellite as of 1 PM showed mostly sunny skies across a
large swath of the Midwest plains within a dry airmass.
Precipitable water from the 12Z Davenport sounding was near the
10th percentile for the date. Surface analysis showed a cold
front progressing into Minnesota with southwesterly winds
shifting northwest behind the front. Tonight the front swill
sweep through dry in most areas. However, there is a small (20%)
chance for a shower this evening mainly across Taylor County
(WI) closer to the stronger synoptic forcing across the upper
Great Lakes. RAP soundings are quite dry at Medford and
instability is minimal, so thunder is not expected.
Tranquil weather will continue through the rest of the Labor Day
weekend and into the first week of meteorological Fall. Canadian
high pressure will settle across the Midwest and Great Lakes through
the first half of the week with dry weather and seasonably cool
temps slowly rebounding towards mid-week. Ensemble spread is quite
small for high temps through Wednesday in the upper 60s and 70s
while lows likely will fall into the 40s for some areas by
Sunday/Monday night, and even upper 30s could not be ruled out in
cooler central Wisconsin locales.
All in all, a relatively benign, dry pattern looks favored over the
next week or two. There is a modest signal for showers around
Thursday as a mid-level trough drags a cold front through the area.
NBM probabilities have modestly increased during this time to 20 to
40%, only slightly lower than a blend of all global ensemble
members. However, moisture return likely will be stunted in the
wake of the dry, high pressure system, possibly limiting
instability. Otherwise, cool northwest flow is forecast towards
next weekend but details of this evolution are less clear right
now.
&&
.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1043 PM CDT Sat Aug 31 2024
VFR conditions and mostly clear skies expected. Winds will
remain out of the northwest for most of the day. Wind gusts
increase for the day with gusts in the upper teens before
diminishing in the evening. Winds will then become light and
variable overnight into Monday.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
DISCUSSION...JM
AVIATION...Cecava
Area Forecast Discussion
National Weather Service Des Moines IA
625 PM CDT Sat Aug 31 2024
...Updated for the 00z Aviation Discussion...
.KEY MESSAGES...
- Pleasant conditions with seasonable temperatures through Labor
Day, then gradual warming trend into Wednesday
- Cold front around Thursday brings the next opportunity (up to
~25%) for any rainfall with below normal temperatures
following behind next weekend
&&
.DISCUSSION...
Issued at 127 PM CDT Sat Aug 31 2024
Early afternoon GOES-East visible imagery shows not a cloud in the
sky over the state, which is a result of large scale subsidence with
high pressure. A moisture starved cold front will pass through the
state tonight bringing in a reinforcing shot of cooler and drier air
for Sunday into Labor Day with highs mainly in the 70s and a crisp
Monday morning with lows in the upper 40s and low 50s. Northwesterly
flow prevails aloft this weekend into early next week as winds flow
around and over an established mid-level ridge over the western US.
Latest HRRR and RAP guidance show that this flow may allow wildfire
smoke from fires in the northern part of Saskatchewan, per Canadian
Wildland Fire Information System, to drift into northern Iowa by
Sunday morning. This high level smoke may cause a bit of a haziness
at sunset.
Otherwise, the weather from Labor Day through the end of next week
has nothing anomalous when examining the NAEFS percentiles, the
ECMWF Extreme Forecast Index, or the Colorado State University`s
machine learning random forest severe weather outlooks. The mid-
level ridge will gradually be pushed eastward as a shortwave trough
at the base of the longwave trough moves eastward mid to late this
upcoming week. This will result in slowly warming temperatures from
Monday through midweek with highs well into the 70s to 80s by
Wednesday. In addition, this trough will bring a surface cold front
into the state around Thursday as shown in the deterministic,
ensemble, and experimental AI guidance such as Graphcast and AIFS.
This front will offer the next opportunity for any rainfall or
storms as well as temperatures going below normal by next
weekend.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 625 PM CDT Sat Aug 31 2024
VFR conditions will persist through the period. Winds will shift
from out of the southwest to out of the north by Sunday
morning.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
DISCUSSION...Ansorge
AVIATION...Hagenhoff
Area Forecast Discussion
National Weather Service Peachtree City GA
752 PM EDT Sat Aug 31 2024
...New 00Z Aviation Discussion...
.SHORT TERM...
(This afternoon through Sunday)
Issued at 249 PM EDT Sat Aug 31 2024
Afternoon convection remains diurnally driven. Coverage should be
greatest north of the Interstate 20 corridor. Strong storms will be
likely with a couple of severe thunderstorms possible. Atmos remains
very unstable with abundant moisture. Lapse rates remain poor, but
DCAPE numbers are 900 J/Kg plus which correlates to the good inverted
v modified afternoon soundings.
A weak frontal boundary will drop south across the CWA tomorrow and
stall across south central portions of the CWA late in the period.
Convection should end up being a little more organized than in
previous days. The airmass will remain the same, but a mid level
trough may add a bit more lift in the upper levels for convection.
The high res models are all over the place with coverage and timing.
Took the timing trends of the HRRR, but leaned towards the higher
coverage of other models. The HRRR seems to have been under
forecasting the coverage of storms the last few days.
NListemaa
&&
.LONG TERM...
(Monday morning through next Friday)
Issued at 249 PM EDT Sat Aug 31 2024
Another shortwave will swing out of Canada into the northeast at the
start of the long term on Monday, reinforcing a surface high
pressure that will set up over the central and east central CONUS.
This will bring another push of continental air towards the CWA,
reinforcing the stalled frontal boundary over central GA. As the
trough swings out into the north Atlantic, the surface high will
shift with it following the AVA. By Tuesday a wedge front looks
likely to push into the CWA as a result of this high sliding over the
northern Appalachians. Flow will continue from the northeast through
at least Wednesday night, and the airmass looks to stick around
Thursday into even Friday, though more uncertainty around that as
another potential system approaches, as well as some uncertainty
around the formation of a coastal low.
As a result of all this, best rain chances through the long term
will be along the stalled frontal boundary in central Georgia. Still,
PoPs remain across much of the CWA each day, as air may have enough
moisture combined with day time heating to get some isolated
thunderstorms to pop. Where things may be a bit too high is in
northern GA after the wedge front moves through, but have chosen not
to modify this too much with this forecast package from the blend.
Blend likely contains models that are not properly handling the wedge
front that may be biasing the precip chances a bit. The other result
of all this will be a return to some (in this forecaster`s opinion)
excellent temperatures. Monday will see 90 to 95 degree highs.
However, cooler air moves in and highs are in the 70s and 80s, with
overnight lows in the 60s and lower 70s.
Lusk
&&
.AVIATION...
(00Z TAFS)
Issued at 740 PM EDT Sat Aug 31 2024
Afternoon shower and thunderstorm activity has been gradually winding
down. However, there are still lingering storms in the AHN area, as
well as on the N side of the Atlanta metro area. HRRR guidance
suggests some lingering showers and storms may continue between the
AHN area and the S portion of the Atlanta metro area, but uncertainty
is high on this solution. Light winds are expected tonight. Winds
will become more W-NW behind a weak frontal trough on Sunday across
the Atlanta area and AHN terminals, with SE-S winds farther S, but
speeds will remain light. More diurnal thunderstorms are expected on
Sunday afternoon.
//ATL Confidence...00Z Update...
Medium for residual shower and thunderstorm development this
evening, high for other elements.
SEC
&&
.PRELIMINARY POINT TEMPS/POPS...
Athens 71 91 70 88 / 20 50 40 40
Atlanta 73 90 73 90 / 20 50 40 40
Blairsville 66 81 65 81 / 30 50 30 50
Cartersville 70 89 68 91 / 30 50 30 40
Columbus 73 95 74 96 / 20 50 50 40
Gainesville 71 88 70 87 / 30 50 30 40
Macon 71 94 72 93 / 20 50 40 40
Rome 71 87 69 91 / 30 50 30 40
Peachtree City 70 90 70 91 / 20 50 40 40
Vidalia 71 93 73 93 / 10 20 30 50
&&
.FFC WATCHES/WARNINGS/ADVISORIES...None.
$$
SHORT TERM...NListemaa
LONG TERM....Lusk
AVIATION...SEC
Area Forecast Discussion
National Weather Service Hastings NE
630 PM CDT Sat Aug 31 2024
.KEY MESSAGES...
- High confidence in dry conditions through at least Tuesday.
Slightly below-normal temperatures overall.
- Rain/t-storm chances return Wednesday night through Thursday.
- Cooler late next week into next weekend.
&&
.DISCUSSION...
Issued at 200 PM CDT Sat Aug 31 2024
Quiet northwesterly flow persists in the upper levels with
riding gradually building to the west. Global ensembles (and the
resulting NBM) all show a 0% chance for any precipitation
through Wednesday morning. Relatively dry air will allow for a
fairly large diurnal temperature swings with overnight lows in
the low 50s and afternoon highs generally in the 80s.
RRFS and HRRR smoke models both show some smoke arriving from
the north-northeast on Sunday, but forecast concentrations are
fairly low (15 ug/m3 or less...which would be in the "Good" to
"Moderate" range). Some minor haze may be visible, but
otherwise no impacts are expected.
Global deterministic models show the next meaningful shortwave
arriving Wednesday night into Thursday. This will bring us
scattered showers and thunderstorms during this timeframe. For
now, the threat for severe weather looks pretty low. The latest
CSU-MLP does not highlight any portions of the area with even a
5% risk.
There are lingering low chances for rain Friday into the
weekend, but overall drier conditions are expected. Cooler air
is also expected to arrive behind the aforementioned shortwave.
It is possible (30% chance) that some areas see temperatures
dip into the 40s. There is even a low chance (5%) that
overnight low temperatures dip into the 30s in northern portions
of the area!
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 630 PM CDT Sat Aug 31 2024
For KGRI/KEAR Airports:
VFR through the period. Winds will go lgt and vrbl late this eve
ahead of a backdoor front. Winds will shift to N then NE early
Sun AM and continue out of the NE around 8-11kt through the
aftn. Confidence: High.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&
$$
DISCUSSION...Mangels
AVIATION...Thies
Area Forecast Discussion
National Weather Service Houston/Galveston TX
557 PM CDT Sat Aug 31 2024
...New AVIATION...
.SHORT TERM...
(This evening through Sunday Night)
Issued at 214 PM CDT Sat Aug 31 2024
Scattered precip will taper off early this evening followed a return
of clouds/stratus overnight. Low level trof/low axis that has been
situated just to our east will begin a slow transition to the south-
southwest Sunday & Sunday night. Though general wx trends will
remain about the same as the past few days (rain near the coast &
offshore late nights and morning...inland during the day), overall
coverage will probably be on the uptick as we get back into some
higher PW air. 47
&&
.LONG TERM...
(Monday through next Friday)
Issued at 214 PM CDT Sat Aug 31 2024
We keep the pattern unsettled into the long term. Current
mid/upper WV imagery along with 500MB RAP analysis show enhanced
vorticity over NW Mexico and SW CONUS due to a mid/upper trough.
This trough will slowly creep over the Lone Star State during the
long term, enhancing large scale lift over a PWAT rich LL
atmosphere. In addition, a frontal boundary is expected to slowly
progress southward, potentially enhancing lift further by mid-
week. Therefore, daily shower/thunderstorm chances are likely to
continue well into the upcoming week. Considering the high PWAT
values, locally heavy showers and thunderstorms will be possible.
Drier air may filter down into SE Texas by week`s end in the
front`s wake. If we`re lucky, maybe we can experience some lower
humidity. But even if we don`t, there is good news on the heat
front. The continued presence of mostly cloudy skies and scattered
showers/thunderstorms should keep afternoon temperatures a little
below normal, with highs generally averaging in the upper 80s
through the long term. High humidity and clouds will keep the
nights on the steamy side with lows in the 70s. IF we are lucky to
experience a less humid airmass by week`s end, then those
overnight lows could drop below 70. But let`s not get excited
about that just yet.
Self
&&
.AVIATION...
(00Z TAF Issuance)
Issued at 557 PM CDT Sat Aug 31 2024
SHRA coverage will decrease this evening. Overnight, should see a mix
of MVFR and IFR ceilings area wide along with increasing SHRA and possible
TSRA coverage closer to the coast (GLS, LBX and maybe HOU) as the coastal
low moves back towards land. Ceilings will lift during the day tomorrow,
but also expect to see increasing SHRA/TSRA coverage further inland
as the day progresses. Could end up with a mix of lingering MVFR ceiling
with rain areas and VFR elsewhere. Expect decreasing rain coverage
tomorrow evening. For winds, light NE to E overnight then approaching
10 knots during the day tomorrow. 42
&&
.MARINE...
Issued at 214 PM CDT Sat Aug 31 2024
Scattered showers and thunderstorms remain in the forecast through
the next week. The highest chance of rain and storms will be
during the overnight and morning hours. Winds will generally be
light to moderate with seas of 2-3ft. However, locally higher
winds and seas are possible within and near any thunderstorms.
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 75 90 74 88 / 10 40 40 60
Houston (IAH) 76 88 75 87 / 40 60 40 70
Galveston (GLS) 79 88 79 86 / 60 70 70 80
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
SHORT TERM...47
LONG TERM....Self
AVIATION...42
MARINE...Self
Area Forecast Discussion
National Weather Service North Platte NE
611 PM CDT Sat Aug 31 2024
.KEY MESSAGES...
- Hot and windy conditions arrive Monday and Tuesday, leading to increased
fire weather concerns each day. A Fire Weather Watch has been
issued for portions of the Sandhills Monday afternoon and
evening. See Fire Weather Discussion below for further
information.
- Temperatures trend cooler Wednesday and beyond with our
potentially first taste of autumn closing out the week with
highs in the 70s.
- Dry conditions persist with our next best shot at meaningful
precipitation across the local area being the middle of the
week at the earliest.
&&
.SYNOPSIS...
Issued at 204 PM CDT Sat Aug 31 2024
Recent GOES-16 WV imagery and RAP 500-mb analysis showed high
pressure anchored across the Desert Southwest with a ridge extending
northwest into the Pacific Northwest. A secondary upper-level high
was noted across the southeastern CONUS with a ridge extending
northeast into New England. An upper-level low pressure system was
spinning in vicinity of the Hudson Bay with a trough extending south
into the Upper Midwest and Great Lakes regions. All of these
features combined has resulted in northwesterly flow aloft
across Nebraska. At the surface, weak high pressure encompassed
a majority of the central CONUS. However, a dry cold front was
sagging southward out of South Dakota across the northern
Sandhills. Ahead of this boundary, strong heating has occurred
with 2 PM CT temperatures ranging from 85 degrees at Ogallala to
93 degrees at Valentine.
&&
.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 204 PM CDT Sat Aug 31 2024
The previously mentioned front will advance through western and
north central Nebraska through this evening and tonight with
Canadian high pressure building in it`s wake. Seasonal low
temperatures in the low to mid-50s settle in across the area tonight
under a clear sky. A pleasant day is in store for the area on Sunday
with a notable cooldown thanks to the frontal passage and light
winds. High temperatures will be in the 80s with plenty of sunshine
to go around on Sunday. As the surface high slides to the east
during the day on Sunday, a disturbance will develop across the
Intermountain West. A surface pressure gradient (SPG) will tighten
in between the two features with strengthening southerly flow on the
western periphery of the high pressure. As a result, southerly winds
will become breezy later in the day on Sunday across the Sandhills,
increasing even further overnight into Monday. Southerly winds
gusting 25 to 35 mph will be common across the Sandhills overnight.
Other than the breezy winds, a near copy and paste forecast as
compared to tonight will be on tap for the area Sunday night with
lows in the 50s.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 204 PM CDT Sat Aug 31 2024
An upper-level trough of low pressure currently ~600 miles off the
coast of northern California will push onshore Monday morning,
nudging the dome of high pressure aloft into the central Rockies.
Surface high pressure will continue across the eastern CONUS with
the previously mentioned surface trough approaching from the west.
This will create an environment supportive of strong winds across
the Sandhills. The strong wind potential Monday into Tuesday is
highlighted by the ECMWF EFI/SoT which has begun to show increased
confidence in an anomalous event potentially impacting portions of
the area. When looking at recent NBM Probabilities, a 75% chance of
wind gusts of 35 mph or greater exists across the northwest
Sandhills. However, when looking at probability of wind gusts
exceeding 40 mph, probabilities drop to 30% or less across the
aforementioned areas. At this time, widespread wind gusts 20 to 30
mph is anticipated with the strongest winds up to 40 mph across the
Sandhills. Temperatures will trend back into the above normal range
Monday and Tuesday as sunny skies and the stronger southerly winds
promote deep mixing. High temperatures on both days will range from
the mid-80s across north central to the upper-90s across northwest
Nebraska. Unfortunately these abnormally hot temperatures
combined with the dry and windy conditions will increase fire
weather concerns for both days, refer to the Fire Weather
Discussion below for more details. Fortunately the upper-level
ridge will be forced to breakdown as the disturbance currently
deepening across the Pacific Ocean advances inland across the
Great Basin into the northern Rockies on Wednesday. This will
drive a surface cold front into the area by Wednesday evening,
allowing highs to trend back into the low to mid-80s on
Wednesday, falling into the 70s through the remainder of the
week. This frontal passage may trigger a few showers or
thunderstorms Thursday into Friday. Confidence is rather low on
precipitation chances during this period and many locations
aren`t likely to see much in the way of wetting moisture. Given
the spread amongst model solutions, cannot argue with the NBM`s
forecast of sporadic slight chance/chance PoPs. The below normal
temperatures closing out the week appear they won`t stick
around as the upper- level ridge builds back in across the
western CONUS through the weekend which will favor above normal
temperatures and dry conditions to return.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 610 PM CDT Sat Aug 31 2024
VFR conditions with maybe a few mid/high clouds expected across
central and western Nebraska through this valid period. Airmass
is quite dry and with temperatures tonight expected to be
roughly similar to last night, do not anticipate any development
of fog or low clouds overnight. There are some subtle hints for
FEW/SCT mid/high clouds tomorrow and with the probability for a
CIG being very low, will go with SKC through Sunday.
A weak front is sagging south through Nebraska this evening with
KVTN already behind the front. This has shifted winds at KVTN to
the northeast and provided a few gusts to around 20kt. Expect
any gusts will diminish quickly this evening as winds gradually
veer around to the east by Sunday morning and remain light
through the end of the valid period. At KLBF winds will remain
light through the overnight period, though after diurnal heating
gets mixing started after daybreak Sunday the effects of the
front will be felt at KLBF with winds becoming easterly with
gusts 15 to 20kt from mid morning through the end of the valid
period.
&&
.FIRE WEATHER...
Issued at 207 PM CDT Sat Aug 31 2024
Elevated fire weather concerns exist across the Sandhills (Fire
Weather Zones 204 and 208) this evening as temperatures climb
into the mid-90s, supporting relative humidity values in the 15
to 20 percent range. However, relatively light winds will limit
fire weather conditions from reaching critical levels.
Fire weather concerns increase Monday and Tuesday across the
Sandhills as continued hot and dry conditions combine with
strong winds. Southerly winds gusting up to 40 miles per hour
combined with relative humidity values falling into the 15 to 20
percent range will present near-critical fire weather
conditions on both days. Given this, a Fire Weather Watch has
been issued for Fire Weather Zone 204 Monday afternoon and
evening. Will continue to monitor the potential for a Watch
issuance for Tuesday as similar conditions are expected.
Beyond Tuesday, low-level moisture will increase with
temperatures falling back to near seasonal values through the
remainder of the week, lessening overall fire weather concerns.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Monday afternoon through Monday
evening for NEZ204.
&&
$$
SYNOPSIS...Viken
SHORT TERM...Viken
LONG TERM...Viken
AVIATION...MBS
FIRE WEATHER...Viken
Area Forecast Discussion
National Weather Service Midland/Odessa TX
510 PM CDT Sat Aug 31 2024
...New AVIATION...
.SHORT TERM...
(This afternoon through Sunday night)
Issued at 239 PM CDT Sat Aug 31 2024
WV imagery this afternoon shows the upper ridge centered over
southwest Wyoming, keeping the focus off West Texas and Southeast
New Mexico. Closer to home, mesoanalysis shows the cold front has
sagged into the Davis Mountains/lower Trans Pecos, where
convection is most likely today and tonight. The rest of the CWA
looks to have a "down" day wrt/precip. NBM came in a little cool
on temperatures yesterday, and model certainty suggests they can
be raised a little both this afternoon and Sunday.
Tonight, w/loss of diurnal heating, convection will slowly
diminish, and look to be over the lower Trans Pecos. With
persistent, but light post-frontal northerly flow, a bit less
cloud cover, and no LLJ, overnight lows will be a degree or so
cooler than this morning`s.
Sunday, temperatures recover a little, but will still average a
couple of degrees below normal under an upper trough. Best rain
chances remain south invof the old frontal boundary. Depending on
what falls down there in the next 12-18 hrs, a flood watch may be
needed.
Sunday night, a cold front arrives, ramping up rain chances,
especially after midnight, aided by a little isentropic upglide.
As with the southern zones, a flood watch may be needed for areas
farther north through Labor Day. Soil moisture products suggest
any extra appreciable rainfall over the next 48 hours will warrant
one. Stay tuned.
&&
.LONG TERM...
(Monday through Friday)
Issued at 239 PM CDT Sat Aug 31 2024
PoPs have decreased in recent NBM runs for Sunday and
consequently so have rain totals by the beginning of next weekend,
which are much closer to 1 to 2 inches now, with accumulations up
to 2.50 inches or greater only apparent now over parts of Pecos
and Terrell Counties. LREF-NH has Grand Ensemble, European ENS
ensemble, and NCEP GEFS ensemble all showing a gradient in rain
totals, with amounts increasing from west to east. Only the
Canadian GEPS ensemble shows a maximum in totals stretching from
the Davis Mountains into the Lower Trans Pecos, with amounts
closer to 3/4 of an inch to 1 inch north and east of the Davis
Mountains and closer to half an inch west and southwest of the
Davis Mountains. We are still forecast to see daily showers and
storms helping to alleviate short term drought concerns, and those
that receive multiple rounds of convection could see 1 to 2
inches or more of rain, but we are not seeing as strong of a
signal for above 2 inches of rain as was seen the past few days.
We will continue to monitor the ensembles and NBM run PoPs and
rain totals into this week.
Widespread rain and storms will be spurred by a weak upper low
present over the area providing lift, coupled with humid, easterly
upslope flow and destabilization from daytime heating. NBM has
begun to show more of a northeasterly component to near surface
winds compared to yesterday, and we will have to see if this
persists, as it could indicate scattered to widespread shower and
storm development lingering longer into next week than currently
forecast. We are still not expecting any widespread severe weather
due to low wind shear.
Decreased geopotential heights and thicknesses over northern
Great Plains are indicated in LREF TLE-NH Grand Ensemble and
clusters as well as GFS, CMC, and ICON models of 500 mb
geopotential and vorticity. This suggests we could see a pattern
of cooler and rainier weather and more frequent cold frontal
passages again by next weekend. Still, this far out exact timing
and placement of any features at the surface and aloft remains
uncertain. High temperatures are still on track to be 10 to 15
degrees below average on Monday resulting from limited daytime
heating owing to the greatest cloud cover and PoPs out of all the
days this week, with many places not rising into the 80s, 60s in
the highest elevations, and 80s limited to regions near the Rio
Grande south and east of the Lower Trans Pecos. A warming and
drying pattern sets in as the upper low moves away from the area
and cloud and rain chances decrease, with high temperatures closer
to if not slightly above normal for early September by the end of
the week into next weekend. However, heating of elevated terrain
and remnant low to mid-level moisture will keep shower and storm
chances in the forecast for most of the area even as PoPs
decrease, especially over southern parts of W TX. By the end of
the week into next weekend, highs in the 80s, 90s near the Rio
Grande, over the northeast Permian Basin and along the Pecos
River, and near triple digit heat along the Rio Grande can be
expected. Low temperatures throughout the long term remain
slightly milder than average and fall into the 60s for most each
night, with some 50s over higher elevations and northern Lea
County Monday night through Wednesday night and mainly higher
elevations Thursday night through Saturday night. Lows each night
continue to fall into the 70s and above for Terrell County into
the Big Bend. Humid easterly winds will keep dew point
temperatures in the 50s and 60s both during the day and night.
&&
.AVIATION...
(00Z TAFS)
Issued at 509 PM CDT Sat Aug 31 2024
VFR conditions will prevail next 24 hours, except in areas of
direct convection. Light, post-frontal northerly flow will
persist, with widespread, low-based cu fields. Latest HRRR
suggests current convection will diminish quickly w/loss of
diurnal heating, and we`ll keep most, if not all, terminals dry.
&&
.PRELIMINARY POINT TEMPS/POPS...
Big Spring 68 88 68 76 / 20 40 70 90
Carlsbad 65 87 65 75 / 10 30 60 70
Dryden 71 88 70 81 / 60 70 80 90
Fort Stockton 67 86 67 75 / 30 70 80 90
Guadalupe Pass 62 76 60 68 / 20 30 50 70
Hobbs 61 87 65 75 / 10 30 60 70
Marfa 62 79 63 73 / 30 80 70 90
Midland Intl Airport 67 87 68 75 / 20 40 70 90
Odessa 67 87 69 75 / 10 40 70 90
Wink 67 89 68 78 / 20 40 70 90
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
TX...None.
NM...None.
&&
$$
SHORT TERM...44
LONG TERM....94
AVIATION...44
Area Forecast Discussion
National Weather Service Raleigh NC
930 PM EDT Sat Aug 31 2024
.SYNOPSIS...
A pair of slow moving cold fronts will move southeast across the
region Sunday afternoon through Monday. High pressure will build
into the mid Atlantic and extend into our region during the middle
of the upcoming work week bringing cooler temperatures.
&&
.NEAR TERM /TONIGHT/...
As of 930 PM Saturday...
Currently monitoring convection to our west that is beginning to
move east of the mountains. While the latest mesoanalysis shows
stable low levels thanks to post-sunset cooling, the HRRR trends of
the last couple runs are now suggesting that an isold shower may in
fact drift into our western-most zones over the next couple hours
before everything dissipates during the overnight hours. As such,
we`ll include a low-end slight-chance PoP for the next few hours
across those zones to address that chance, but any rain that does
fall across our western zones through 1 AM or so should be light and
very brief. Otherwise, look for periods of clouds to cross central
NC overnight from the west and northwest, so we don`t believe that
fog and low clouds will be as extensive as earlier this morning, but
nonetheless the risk for some patchy fog exists between 09-12Z, esp
where the clouds can clear out for a time overnight. Lows from the
upper 60s in the cooler spots to lower 70s elsewhere.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 205 PM Saturday...
A large mid and upper level vortex will move slowly east across
Ontario and Quebec on Sunday and Monday with a broad cyclonic flow
across the Great Lakes and Northeast. Further south, a modest trough
extends from NY southeast into the western TN Valley on Sunday
morning with the trough making slow eastward progress into western
VA and western NC on Sunday night. The trough will move slowly east
reaching the Carolina coast by Monday evening. At the surface, a
pair of frontal systems will move southeast from the OH Valley into
the mid-Atlantic and Carolinas during the period. The initial front
will weaken a bit into a surface trough on Sunday as it moves into
western VA and NC and becomes engrossed in a chaotic convective
episode. The primary front will move into the southern Appalachians
on Sunday night and then move into central NC on Monday morning and
then settle south and east reaching SC and GA by Tuesday morning.
Sunday morning will start with considerable clouds and perhaps some
fog. With heating, the atmosphere will become moderately unstable
and scattered convection developing around midday with the
convection growing in coverage and intensity during the afternoon
and evening with the convection shifting east with time. Expect the
convection to initiate and organize in line clusters often oriented
northeast to southwest. With forcing for ascent continuing for a
period of time and deep moisture with PWs in the 1.8 to 2.4" range,
multiple rounds of convection may move across the area resulting in
a risk for heavy rainfall and flooding. The wind field is rather
light and generally characterized by mainly westerly flow a t 15 to
25kts resulting in 0-6km shear values of 20 kts or less. SPC has
outlined the area in a marginal risk, with precip laden downburst
winds the primary threat. Convection will transition east during the
evening and linger a bit into the overnight before fading late.
Highs on Saturday will range in the upper 80s to lower 90s with lows
around 70.
As the front and mid/upper level trough shifts east, rain chances
will decrease on Monday and the convective coverage will be focused
across the Coastal Plain and Sandhills. Given a good deal of
cloudiness and a cooler air mass filtering into the area, afternoon
instability will be more limited and focused across the east and
southeast. Accordingly, the risk of a strong storms is much more
limited and confined to the Coastal Plain and Sandhills. Further
north and west, there is just a slight chance of a shower or storm
across much of the Piedmont with some intervals of sunshine. Highs
will be a little tricky with the cooler and drier air mass working
into the region. Highs should range in the lower and mid 80s. Lows
on Monday night will be noticeably cooler and range in the lower to
mid 60s. -Blaes
&&.
.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 305 PM Saturday...
The extended forecast will begin with below normal temperatures
thanks to a cold-air damming scenario with high pressure centered
over New York allowing a ridge of high pressure to extend into North
Carolina. Meanwhile, there will be widespread rain along the Gulf
Coast with low pressure centered over Mississippi. Cannot rule out
an isolated thunderstorm across southern Sampson County, but
otherwise it appears that rain should remain south of the area
Tuesday as the front from the holiday weekend sinks to the south. It
appears that the rain shield should shift slightly farther to the
north on Wednesday, with slight chance pops across southern tier
counties Wednesday afternoon. As the midnight shift stated in their
discussion, forecast confidence remains low from Thursday on with
the GFS/GEFS and ECMWF/EPS showing different synoptic scenarios.
While the GFS shows low pressure moving northeast from New Orleans
Friday morning to Charleston, SC Saturday morning and continuing
northeast, the ECMWF develops a low along the South Carolina coast
Friday morning and has a deeper low off the Delmarva Peninsula
Saturday morning. Each model families would have its own specific
precipitation characteristics - for now, will stick with a general
forecast of chance pops Thursday, Friday, and Saturday. High
temperatures will slightly increase through the period, and Saturday
will be the warmest day with highs ranging from the mid 70s to the
mid 80s.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
As of 745 PM Saturday...
Generally VFR conditions are expected tonight through 18z Sunday.
The exception will be the chance of late night mostly MVFR fog
between 09z and 12z Sunday. After 18z Sunday, there is a chance of
showers/thunderstorms. Confidence in specific timing and location
were too low to place in the TAF at the moment.
After 00z/Monday through Thursday... Higher precip chances
late Sunday through Monday will result in the chance of sub-VFR
conditions through the time period. As the frontal boundary moves
through the region late Monday, VFR conditions are expected
to return late Monday into early Tuesday. Generally VFR conditions
are expected Tuesday and Wednesday, with a chance of MVFR conditions
in scattered showers and storms Thursday.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Badgett
NEAR TERM...np
SHORT TERM...Blaes
LONG TERM...Green
AVIATION...Badgett
Area Forecast Discussion
National Weather Service Reno NV
144 PM PDT Sat Aug 31 2024
.SYNOPSIS...
* There continues to be a slight chance of showers and
thunderstorms in the forecast for this afternoon in the eastern
Sierra south of Tahoe with additional showers and storms
possible on Sunday for west-central NV.
* Increasing winds will produce critical fire weather conditions
on Labor Day, along with impacts to aviation and recreation.
* Temperatures cool briefly to near average after the holiday
before warming to above average by the end of the next week.
&&
.DISCUSSION...
The latest RAP analysis shows the CWA currently underneath an weak
trough embedded in the western portion of a upper air ridge with a
closed low trailing the ridge off the Pacific Coast. The latest
surface observations along with satellite imagery report
scattered clouds developing generally south of I-80 this afternoon
with dry conditions. Going through the remainder of today,
forecast guidance forecasts the Pacific trough to progress
eastward a bit allowing for the CWA to have a generally southerly
flow as the weak trough departs through the upper air flow away
from the CWA. When looking at the latest run of the HRRR, slight
chances (~15%) for isolated showers and thunderstorms look to
appear for areas generally south of I-80 (where the clouds are
developing) beginning around 2-3 PM PDT that start to diminish
around 10 PM PDT. Minimal QPF values are in the forecast with
these showers. While thunderstorms do not look to be severe at
this time, there could be some gusty outflows should a storm
occur. Tonight`s low temperatures look to range between the
middle 50s and middle 60s in the lower valleys while the higher
elevation areas may see lows ranging between the lower 40s and
middle 50s.
Going through the rest of the holiday weekend, ensemble guidance
shows the Pacific low continuing its eastward progress with the CWA
being underneath the forward part of its influence by Sunday
afternoon. The low is expected to open up into a trough over
central OR during the afternoon hours of Labor before having its
axis pass over the CWA during the evening hours. With this upper
pattern setup, breezier winds out of the southwest can be expected
in the afternoon which may allow for some blowing dust in desert
portions of western NV. In addition, portions of the CWA closer to
OR border see slight chances (~15%) for showers and thunderstorms
on Sunday night ahead of an approaching cold front. This cold
front continues to push forward from the Pacific Northwest on
Labor Day causing some increased southwesterly wind gusting up to
around 30 to 40 mph within the CWA during the day. Those with
outdoor plans should monitor for forecast updates as this could
produce more blowing dust in desert areas, choppy conditions on
area lakes, and critical fire weather conditions (see Fire Weather
section for more info). A Fire Weather Watch continues for
portions of the region as a result. Seasonably warm daytime
temperatures expect to continue through the holiday.
On Tuesday, forecast guidance shows the upper air trough departing
eastward away from CWA while a ridge trails it coming in from the
west. This ridge is forecast to move over the western CONUS on
Wednesday and Thursday governing the general upper air pattern. A
weak trough is then seen making an appearance over northern CA in
the middle of Friday which then changes the CWA`s upper air flow to
more southwesterly. With this evolution of the upper air pattern, a
brief cooldown in temperatures along with dry conditions are in the
forecast on Tuesday following the cold frontal passage. This is
followed by a return to seasonably warm temperatures for the
remainder of the work week along with a continuation of the dry
conditions. Breezier winds may be in the forecast on Friday with the
change in the upper air pattern, so will monitor this going forward.
-078
&&
.AVIATION...
VFR conditions are anticipated for the REV TAF sites for today with
the primary concern being chances (~15%) for isolated showers and
thunderstorms in the region generally between 31/21Z - 01/03Z. Best
chances look to be for areas along the CA/NV border and south of I-
80 (KMMH, KTVL). Not anticipating a reduction in flight rules, but
will continue to monitor and amend TAFs if needed.
Southwest to west winds expect to increase Sunday and become
stronger on Monday when gusts reach 25-35kts, inducing periods of
moderate turbulence and LLWS issues for area terminals. Portions of
the region closer to the OR border see some chances (~15%) for light
precipitation in the form of isolated showers between 02/00Z -
02/12Z. The latest HRRR also projects some potential near-surface
smoke from the Coffee Pot Fire in CA moving into Mono County on
Sunday, so will be monitoring that in case it starts to affect area
visibility. -078
.FIRE WEATHER...
Changes: Fire Weather Watch start time adjusted earlier due to
timing of the frontal passage favoring the late morning and early
afternoon.
There is a 10-15% chance for thunderstorms this afternoon generally
south of US-50, with main concerns being dry lightning strikes and
gusty outflow winds. More storms are possible generally east of US-
95 on Sunday, though instability is lacking. The main story this
weekend continues to be the Labor Day wind event.
The forecast remains on track for a weather system to bring
increasing southwesterly winds by late Sunday afternoon, followed by
widespread gusty winds on Monday. While fire weather conditions will
be elevated across the entire region on Monday, the main concern
remains for conditions reaching critical thresholds across portions
of northeast California and far western Nevada from late Monday
morning into the evening hours. Probabilities continue to increase
for the aforementioned areas to see a 3-6 hour period of wind gusts
30+ mph overlapping with RH in the single digits to low teens. Some
locations have a 30-40% chance to see gusts upwards of 40 mph,
mainly far eastern Lassen and far northern Washoe counties. Whitlam
&&
.REV Watches/Warnings/Advisories...
NV...Fire Weather Watch from Monday morning through Monday evening
NVZ420-458.
CA...Fire Weather Watch from Monday morning through Monday evening
CAZ270-278.
&&
$$