Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/25/22
Area Forecast Discussion
National Weather Service Boston/Norton MA
1004 PM EST Thu Nov 24 2022
.SYNOPSIS...
A cold front will bring scattered showers Friday, along with
blustery conditions through Saturday morning. High pressure
brings dry and seasonable conditions on Saturday. Low pressure
tracking to our west and north bring showers and gusty winds to
the region late Sunday through early Monday. Mainly dry,
tranquil weather extends through Wednesday ahead of a potent
cold front sometime mid to late week.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
955 PM Update:
With onset of thicker mid to high clouds being delayed, another
night of efficient radiational cooling acorss interior MA/CT/RI
and in the more sheltered areas in eastern MA/MVY. Light/decoupled
winds has again ensued with significant spatial differences in
these areas. Temps range from the mid 20s in northern MA to the
middle to upper 40s along the southern coast, much of the Cape
and Nantucket. Tried to better show this in the temperature
grids using some of the bias-corrected HRRR given generally
similar conditions over the last couple/few nights.
Looks like thicker cloud cover to arrive in the next few hrs,
which should facilitiate easing temperature cooling and
eventually a rise in temps and dewpoints into the pre-dawn/early
AM hrs. Thus lows should take place in the next couple hrs or so
before warm advection ensues on strengthening 950-850 mb SWlys.
Haven`t made any changes to PoPs/Wx as yet and will reassess
when the full 00z NWP suite arrives. However fcst soundings show
incomplete lower-column saturation across western MA, Berks and
western CT even by sunrise. Given this and regional composite
radar trends showing showers still back in Ohio, may look to
shift back the hourly- increase in PoP toward the 11-13z window
in our western cities and towns.
Previous discussion:
High pressure moves offshore as northern stream trough and attendant
cold front approaches from the Great Lakes. Mid/high clouds will be
increasing through the night and while a stray shower couldn`t be
ruled out across the far western zones towards daybreak, dry weather
will be the rule as deeper moisture remains to the west overnight.
Temperatures will be somewhat all over the place. Expect lows in
the upper 20s to mid 30s across the typically cold interior
spots, which will likely reached during the first half of the
night. Then as southwest flow increases and clouds thicken,
temperatures will stabilize and even rise a few degrees
especially across southeast MA. Locations like Nantucket may
even approach 50F.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Friday...
Not as nice of a day as Thanksgiving Day, but not a washout
either. In fact, some places might not get much rain at all,
especially across portions of northern MA. Best chance for
steadier showers/light rain appears to be across southern zones.
As the 35-45 kt low-level jet overspreads the area, could see
steadier showers/rain towards southeast MA, especially Cape Cod
and the Islands. And due to the warm air moving in aloft, will
need the showers to help overcome the inversion to bring down
the stronger winds. Winds will gradually increase during the day
but the stronger gusts should arrive after sunset as the flow
turns westerly and colder air filters in aloft.
Temperatures wise, quite a bit milder with daytime highs rising to
above normal for a change given the cold pattern that we experienced
for the past 10 days. For reference, typical highs for the last
week of November are in the mid 40s to near 50. With 925mb
temps rising to +3 to +8C from northwest to southeast, expect
highs to top out in the mid 40s to mid 50s, with a few upper 50s
readings not out of the question across the Outer Cape and
Nantucket despite plenty of cloud cover.
Friday night...
Winds will increase overnight, with 35-40 mph gusts possible as
inversion is overcome and lapse rates steepen. Don`t have enough
confidence to hoist Wind Advisories but parts of the high terrain as
well as Cape and the Islands could see 45 mph gusts at times. In
addition, there could be some upslope showers and the thermal
profile would be cold enough for snow to be mixed in above 1500 ft.
No accumulations expected, however. Otherwise, most locations will
see mostly dry weather and blustery conditions.
Temperatures wise, the gusty to blustery winds will suppress
radiational cooling and support fairly uniform low temperatures
in the upper 20s to low 30s (except mid to upper 30s Outer Cape
and Nantucket) across southern New England Saturday morning.
However, the wind chill factor will make it feel more like the
upper teens to mid 20s.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
Highlights
* Tranquil Saturday gives way to showers/rain Sunday evening.
* Gusty winds and gale force conditions likely overnight Sunday into
Monday morning
* Seasonable, dry conditions to start the work week ahead of a
strong cold front sometime mid to late next week.
Saturday and Sunday...
Modest mid level ridge builds in for Saturday bringing dry
conditions to the region. Friday night`s gusty winds will gradually
subside through the day as high pressure centers itself east of
southern New England. Seasonable conditions expected with 925mb
temperatures a few degrees either side of zero. 925mb temperatures
climb to between 5 and 7C by late Saturday afternoon thanks to WAA
on SW flow aloft ahead of an approaching cold front. Surface winds
will prevail more from the west, which will limit temperatures from
achieving their full potential late Saturday afternoon.
A significant layer of dry air, pretty much from the surface to
500mb, will be in place late Saturday through early Sunday, with
PWAT anomalies around 40% of normal. Low pressure will track to our
west on Sunday over the Great Lakes, keeping us in the warm sector
for any precipitation Sunday afternoon. The aforementioned dry layer
will pose a significant hurdle to developing showers and steady rain
on Sunday, with guidance indicating precip will not be able to
overcome the dry air and saturate the column until about 18Z Sunday.
Rain will gradually overspread southern New England from west to
east between 18 and 21Z Sunday. Total QPF from this system continues
to trend drier with the GEFS ensemble showing a 0% probability of
0.5" of QPF or greater between Sunday evening and Monday morning.
Even the ECMWF ensemble probs, which have leaned wetter over the
past few forecast cycles, indicate a 20% chance or less of 0.5" of
QPF, isolated to the south coast, Cape, and Islands. Expecting
between 0.25 and 0.5" of QPF out of this system; WPC QPF supported
this trend with a local maximum of just under 0.5" across Cape Cod.
Winds will be the greater concern Sunday night into Monday morning,
with both the ECMWF and GEFS ensemble probs showing near 100%
confidence in Gale force gusts across our waters around 06Z Monday.
A very robust 925mb jet will be in place between 00Z and 12Z Monday,
with 925mb winds of 60kt over the waters south of Long Island.
Fortunately, we typically do not see mixing achieve it`s maximum
potential on SW flow, but given the strength of the jet, model
soundings indicate that gusts up to 40 kt are on the table. ECMWF
probs even suggest a 10-20% chance of 50kt+ gusts over portions of
our southeast outer waters. The jet will be centered over the
waters, so not anticipating any sort of advisory level gusts over
interior southern New England. With that said, it will certainly be
a gusty evening for most!
Monday into mid week...
Showers and rain associated with the low passing to our north and
west will diminish between 06-12Z Monday. Shortwave approaching from
the west may initiate some showers across the high terrain during the
day on Monday, but surface temps in the upper 40s and 50s indicate
any precip would fall as rain. Other than isolated showers, most of
the region will be dry for the duration of Monday.
Broad mid level trough sets up over our area late Monday night and
Tuesday bringing dry, tranquil weather to the region. Surface high
pressure to our south will allow southerly winds to develop,
advecting above normal temperatures into the region for Wednesday
ahead of another cold front eyeing our area sometime mid to late
week. While this cold front is still about a week out, there is a
consistent signal that a strong wind event could be associated with
this front with both the GFS and ECWMF in agreement that a 60-70kt
925mb jet has the potential to set up over portions of southern New
England. While we will need to keep an eye on this system, it does
appear that it could be the most potent of the long term period.
Trends in guidance will need to be monitored carefully to determine
the potency and timing of this system.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
Forecaster Confidence Levels:
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
2030Z TAF Update...
Through 00z: High confidence.
VFR. SW winds around 5-10 kt.
Tonight: High confidence.
Lowering, generally VFR cloudiness through the period; low prob
of developing MVFR with possible light -SHRA toward daybreak
across far western MA. SW winds increasing to around 10-15 kt;
low- level jet of 35 to 40 kt crossing southern New England
could lead to low- level wind shear around and after 06z Fri.
Friday: High confidence in trends, moderate on the exact timing.
Generally MVFR ceilings with advancing light -SHRA associated
with cold front. Wet runways possible but total rain looks
quite light and showery in nature. Conditions could improve to
more MVFR/VFR as soon as mid afternoon with rain ending by mid
to late afternoon, lingering till early evening across Cape and
the Islands. SW winds 10-15 kt with continued intervals of low-
level wind shear before winds turn W around mid to late
afternoon with increasing gusts to 25 to 30 kt.
Friday night: High confidence.
Improving to VFR with NW winds 15-20 kt and gusts 30-35 kt with
isolated 40 kt possible. Mostly dry except for isolated upslope
light snow showers across the east slopes of the Berkshires.
KBOS Terminal...High confidence in TAF.
KBDL Terminal...High confidence in TAF.
Outlook /Saturday through Tuesday/...
Saturday: VFR. Windy with gusts up to 35 kt.
Saturday Night: VFR. Breezy.
Sunday: Mainly VFR, with areas MVFR possible. Breezy. RA
likely.
Sunday Night: Mainly MVFR, with local IFR possible. Windy with
gusts up to 35 kt. RA likely.
Monday: Mainly VFR, with local MVFR possible. Breezy. Slight
chance RA.
Monday Night: VFR. Breezy.
Tuesday: VFR.
&&
.MARINE...
Forecaster Confidence Levels:
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
330 PM Update:
Overall high confidence.
Gale Warnings are in effect across most waters for Friday
afternoon through Saturday afternoon. Southwest gusts preceding
a cold front Friday could at times get close to Small Craft
Advisory criteria along with periods of mostly light rain.
Gusts increase to gale force by Friday evening after the
frontal passage as winds shift to northwest with gusts 30-35 kt
and isolated 40 kt possible. Wave heights also increase to 5-9
ft overnight Friday into early Saturday morning.
Outlook /Saturday through Tuesday/...
Saturday: Low risk for gale force winds with gusts up to 35 kt.
Areas of rough seas.
Saturday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of seas approaching 5 ft.
Sunday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Areas of seas approaching 5 ft. Chance of rain.
Sunday Night: Moderate risk for Small Craft Advisory winds with
gusts up to 30 kt. Areas of rough seas. Rain.
Monday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Rough seas up to 9 ft. Slight chance of rain.
Monday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Rough seas up to 9 ft.
Tuesday: Winds less than 25 kt. Areas of seas approaching 5 ft.
&&
.TIDES/COASTAL FLOODING...
High astro tides combined with increasing southwest flow and rising
wave heights could lead to pockets of nuisance to very isolated
minor coastal flooding for the late Friday morning high tide.
Boston and Nantucket astro tides peak at 11.7 ft and 4.1 ft late
tomorrow morning respectively, so with total tide departure of
around 1 ft, this would put both locations on the cusp of minor
coastal flooding. Hence, have issued a Coastal Flood Statement
for Nantucket, Cape Cod and Boston Harbor to the North Shore
where the best chance for isolated pockets of minor coastal
flooding could occur on Black Friday.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 1 PM Friday to 1 PM EST Saturday for
ANZ230-236.
Gale Warning from 1 PM Friday to 1 PM EST Saturday for
ANZ231>235-237-250-251-254>256.
&&
$$
SYNOPSIS...Chai/KS
NEAR TERM...Loconto/Chai/KS
SHORT TERM...Chai
LONG TERM...KS
AVIATION...Loconto/Chai/KS
MARINE...Loconto/Chai/KS
TIDES/COASTAL FLOODING...
Area Forecast Discussion
National Weather Service El Paso Tx/Santa Teresa NM
506 PM MST Thu Nov 24 2022
...New AVIATION...
.SYNOPSIS...
Issued at 330 PM MST Thu Nov 24 2022
An approaching upper level storm system will bring snow to area
mountains and a mix of rain and snow to the lowlands, mainly east
of the Rio Grande tonight and into Friday. Snow totals in the
Sacramento Mountains could approach or exceed one foot of snow.
For the lowlands east of El Paso we could see one to three inches
of snow in Hudspeth County. El Paso and Las Cruces could see a
trace to an inch or two of snow. Friday will be windy, cloudy,
and cold with high temperatures running well below average. For
Saturday and Sunday, we will see the sun return and our high
temperatures will begin a warming trend. We will see high
temperatures near average for next Monday and Tuesday, before more
cold air arrives to drop our high temperatures below average
again for next Wednesday.
&&
.SHORT TERM...
(This evening through Friday Night)
Issued at 330 PM MST Thu Nov 24 2022
A major winter storm looks on track to affect our region with the
harshest impacts expected to be across the higher terrain of
Hudspeth and Otero Counties plus the Black Range. As of 1pm, the
UL`s low large center was over Southern NM with water vapor imagery
showing increasing diffluence and deformation across our northern
zones into ABQ`s CWA. Radar and webcams show snow has begun for the
Black Range, portions of the Gila, and Sacramento Mountains. This is
only the beginning. This UL low will only slowly continue to shift
south, centering over the International Border late tonight,
drifting over Hudspeth County and adjacent areas of Northern
Chihuahua throughout the morning, before finally shifting east into
Big Bend by Friday evening. It should finally be far enough into
West Texas for its impacts to exit our CWA Saturday morning.
The main impact from this system will be heavy snowfall. Model
guidance continues to show the heaviest snowfall across the
Sacramento Mountains. Here the best dynamics and moisture tap plus
some upslope component will set the stage for several inches of snow
to accumulate through Saturday morning. East slope areas could see
well over a foot of snow with Cloudcroft expected to finish just
below that mark. The Black Range also looks to be in a favorable
position to get heavy snow tonight. A strong upslope component there
will allow some of the higher peaks to approach a foot of snow as
well. Emory pass could see some hefty totals. Elsewhere, much less
snow and fewer impacts are expected. The Gila could see some light
totals, but models are clueless to the current showers on radar.
Hudspeth county will be closer to the low and colder dynamics.
Accumulating snow is likely with 1 to 4" expected with much higher
totals possible across the Mountains. For the remainder of the
lowlands, models are struggling, but 12z guidance has backed off
some of the higher totals. Rain and snow will be possible but
amounts are uncertain. We could very well see no rain or snow for
our biggest population centers including Alamogordo, Las Cruces, and
El Paso.
Wind will be another concern for the West Slopes of the Gila and
Sacramento Mountains. HRRR and to lesser degree NAM Nest are
indicating winds could gust over 50 MPH. These winds combined with
heavy snow could lead to white out conditions.
Last note, these impacts will cross into much of Eastern New Mexico
and West Texas. If you plan on traveling tomorrow and even into
Saturday, be sure to check the forecasts of our sister offices:
Albuquerque, Midland, Lubbock, and Amarillo.
&&
.LONG TERM...
(Saturday through next Wednesday)
Issued at 330 PM MST Thu Nov 24 2022
This extended forecast picks up on Saturday as the upper level
storm system that will bring heavy snow to area mountains and
even some lowland snows, will be pushing off to east. As the low
exits east, it will take with it the clouds, wind, and
precipitation. We will begin a warming trend on Saturday, as our
afternoon highs will warm around 10 degrees from the highs we will
see on Friday, but Saturday`s high temperatures will still run a
few degrees below average. For Sunday and Monday, our quiet
weather will continue as a zonal flow (west to east) aloft, brings
in some warmer high temperatures. High temperatures both days will
run at, or a little above average.
For Tuesday, another upper level trough will approach the region.
This next trough looks to move across northern New Mexico, which
would limit our precipitation chances to the mountains, but it
would give us a windy afternoon. It is a little early to be
talking about wind speeds, but some wind highlights may be needed
for Tuesday. Cooler air will filter in behind the trough so that
high temperatures on Wednesday will again be several degrees below
average.
&&
.AVIATION...
(00Z TAFS)
Issued at 446 PM MST Thu Nov 24 2022
VCSH currently being seen at KELP and KLRU tonight. Showers are
expected to continue the next few hours before activity diminishes
around midnight for these terminals. KTCS has the best chance to
see continued VCSH and MVFR conditions as cloud bases begin to
drop tonight. KLRU and KELP may eventually see MVFR conditions as
the system progresses south. KELP may see another shot of VCSH in
the morning and afternoon hours. Breezy north/northeasterly winds
will persist tonight with speeds generally around 15-20G25-30KT.
&&
.FIRE WEATHER...
Issued at 330 PM MST Thu Nov 24 2022
A major winter storm will bring heavy snowfall to the Sacramento
Mountains and the Black Range. The Gila Wilderness could see some
light snow too. For the lowlands, rain and snow look less certain,
but rain/snow showers are possible tonight through much of the day
tomorrow. With the cool air and possible showers, this will help
keep min RH values into the 30s and 40s. The highest lowland values
will be across Hudspeth County where rain and snow are most likely.
Winds will remain elevated with 20-foot winds of 10 to 15 mph with
higher winds tonight across the west slopes of the Blacks and
Sacramento Mountains. Vent rates will range poor to good on Friday.
This system exits on Saturday, which will begin a warming and drying
trend. Min RH values will decrease through Monday while afternoon
highs warm to near seasonal levels Saturday and Sunday and above on
Monday. Min RH values will drop into the teens for most lowland
locations. Winds will be breezy Saturday and Monday, but no critical
conditions are expected.
&&
.PRELIMINARY POINT TEMPS/POPS...
El Paso 36 47 33 61 / 30 40 30 0
Sierra Blanca 30 36 28 50 / 20 50 50 0
Las Cruces 32 49 26 58 / 20 30 10 0
Alamogordo 30 47 26 53 / 40 40 30 0
Cloudcroft 15 23 16 34 / 70 60 40 10
Truth or Consequences 32 49 28 59 / 50 30 10 0
Silver City 28 49 28 54 / 20 10 0 0
Deming 33 52 25 61 / 10 20 10 0
Lordsburg 28 55 27 59 / 0 10 0 0
West El Paso Metro 35 46 32 59 / 30 40 30 0
Dell City 32 41 28 54 / 40 50 60 10
Fort Hancock 32 42 30 58 / 10 40 40 0
Loma Linda 30 38 28 51 / 30 50 40 0
Fabens 34 45 30 59 / 20 50 30 0
Santa Teresa 32 45 28 58 / 20 40 20 0
White Sands HQ 34 48 31 58 / 20 40 20 0
Jornada Range 33 48 27 57 / 20 30 20 0
Hatch 33 51 26 62 / 20 30 10 0
Columbus 33 50 28 60 / 20 20 10 0
Orogrande 31 45 28 54 / 40 50 30 0
Mayhill 20 29 21 44 / 80 70 50 10
Mescalero 20 34 20 43 / 70 50 40 10
Timberon 19 32 18 41 / 60 60 50 10
Winston 25 43 25 57 / 40 20 10 0
Hillsboro 28 49 25 61 / 40 30 10 0
Spaceport 30 49 24 57 / 30 30 10 0
Lake Roberts 22 47 21 54 / 20 10 0 0
Hurley 28 52 25 58 / 10 10 0 0
Cliff 23 59 19 62 / 10 10 0 0
Mule Creek 25 54 26 56 / 10 0 0 0
Faywood 30 49 27 58 / 20 20 10 0
Animas 28 53 25 62 / 0 0 0 0
Hachita 28 52 24 60 / 10 10 0 0
Antelope Wells 28 49 26 61 / 0 10 0 0
Cloverdale 28 46 26 55 / 0 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
TX...Winter Weather Advisory from midnight tonight to midnight MST
Friday night for TXZ420>422.
NM...Winter Storm Warning until midnight MST Friday night for
NMZ414>417.
&&
$$
SHORT TERM...99
LONG TERM....99
AVIATION...37-Slusher
Area Forecast Discussion
National Weather Service San Francisco Bay Area
324 PM PST Thu Nov 24 2022
.SYNOPSIS...Thanksgiving weather has mild and dry conditions on
the menu with a side of above normal temperatures this afternoon.
Dry conditions persist through the end of the week while
temperatures gradually cool. A trough will dig southward into
NorCal early next week, bringing cooler temperatures to the area.
Morning lows will be especially chilly next week for the interior
portions of our area.
&&
.DISCUSSION...as of 02:15 PM PST Thursday...Sunny skies on this
Thanksgiving Day as a ridge of high pressure resides over the
area. Offshore flow continues for higher terrain with gusts around
15-20 mph are currently being observed in the interior North Bay
Mtns and the East Bay Hills. The WMC-SFO (offshore) gradient is on
the decline but still remains moderate at around -13 mb (peaked
at -17 mb this morning). The gradient will continue to fall and as
such offshore winds will diminish through the day. With the
stronger offshore flow this morning, minimum RH in the North Bay
Mtns dipped into the low teens. Adjusted relative humidity
forecast by blending in the HRRR to better capture dry conditions
at higher terrain for today and tomorrow. Offshore flow has also
aided in warming of temperatures on the downsloping side of higher
terrain. High temperatures are on track to be in the low to mid
70s this afternoon. With these dry and locally gusty conditions
lingering through the afternoon, be sure to continue to use
caution and remember to be that one less spark in order to prevent
a wildfire.
If planning to head to the beach today, long period northwest
swell will be arriving later today which will bring increased risk
of sneaker waves and rip currents. See BEACHES section below for
more details on the Beach Hazard Statement that is currently in
effect.
A shortwave trough is on track to dip down into NorCal early
Saturday morning, which will kickstart a cool down for the Bay Area
and Central Coast. Weak onshore flow will also return as a response,
bringing the return of cooler marine air this weekend.
By early next week, a robust trough will dip down from Canada into
the Intermountain West. WPC Cluster Analysis ensemble members
continue to be in good agreement on timing/strength of initial
trough coming down on Monday. Rain chances are now a distant
memory, unfortunately, as sufficient moisture supply is no longer
accompanying this trough. PoPs on Monday are around 10%, so higher
confidence that we will not see rain from this system. Cold air,
however, will be associated with this trough, so expect
temperatures to be cooler next week and below seasonal averages
(max temps in the upper 50s/lower 60s). High confidence of morning
lows will getting chilly next week, with a good part of the
interior dipping into the low 30s. Looking beyond to early
December, unsettled weather continues as troughy pattern persists.
&&
.AVIATION...as of 03:15 PM PST Thursday...For the 00Z TAFs. High
confidence for VFR conditions to prevail through the TAF period
for most terminals. The exception will be at KSTS where
persistence supports early morning fog between 09Z-15Z Friday.
Otherwise, light winds across the region with slightly stronger
offshore flow to around 10kt-15kt for terminals such as KLVK and
KAPC, diminishing in the early evening hours.
Vicinity of KSFO...VFR. Light offshore flow to persist through
much of the TAF period with higher confidence of onshore winds
developing by 21Z Friday.
KSFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR. Generally light and variable winds
at KMRY through the TAF period while southeasterly drainage winds
about 10 kts will increase after midnight around KSNS. Moderate
confidence in light onshore flow returning early-to-mid Friday
afternoon.
&&
.BEACHES...as of 03:20 PM PST Thursday...A long period northwest
swell persists through this evening with periods of around 19 to
21 seconds. This will cause an increased risk of sneaker waves and
strong rip currents for northwest facing beaches lasting until
late tonight. Large, unexpected waves can run-up far onto the
beach without warning, sweeping people into the sea from rocks,
jetties, and beaches. These waves can also move large objects such
as logs, crushing anyone caught underneath.
Don`t be fooled by an ocean that looks calm. There can be
30 minutes of small waves before a sneaker wave strikes. Avoid
rocks and jetties. Avoid steep beaches. Stay much farther back
from the water and never turn your back on the ocean. Do not let
pets or children unattended near the water.
&&
.MARINE...as of 01:56 PM PST Thursday...Light northerly to
offshore winds will persist through the end of the week. A passing
weather system will bring the return of northwest winds on
Saturday that will strengthen through the weekend and prevail into
next week. Northwesterly swell will also build into the weekend
and combine with strengthening wind waves to produce hazardous
seas for small craft into early next week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.Tngt...NONE.
&&
$$
PUBLIC FORECAST: McCorkle
AVIATION: Behringer
MARINE: RGass
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Area Forecast Discussion
National Weather Service Blacksburg VA
726 PM EST Thu Nov 24 2022
.SYNOPSIS...
High pressure slides east tonight. Low pressure over the
southeast will bring rain to the area Friday, followed by a
brief dry period for Saturday. Another storm system moves across
Sunday with more rain.
&&
.NEAR TERM /THROUGH FRIDAY/...
As of 710 PM EST Thursday...
Slight adjustment to the arrival time of rain...
Hi-Res models bring isolated to scattered rain into northern
North Carolina and southern Virginia after midnight. Made
adjustments to the timing of the rain based on the FV3 and HRRR
guidance. Only minor changes to temperatures tonight.
Previous discussion:
High pressure across the region slide east tonight. A wave of low
pressure will track northeast across the Southeast Friday.
Warm advection aloft will bring more clouds in from the south
overnight with the layer moistening up. With the dry airmass
across the region, as demonstrated by 0.24 inch PWATs on this
morning 12z RNK sounding, it will take some time.
Low temperatures tonight will be warmer than this morning with
readings from the mid 30s in the mountains to the lower 40s in
the Piedmont. A surface low over the Gulf Coast states will move
across the southeast US Friday. Rain from the low will cover
the North Carolina and Virginia Piedmonts, while rain from the
northern cold front will move into the western mountains. The
departure of the rain or drying out is quick Friday afternoon.
While some clouds and showers linger in the western mountains.
High temperatures Friday will range from the mid 40s in the
northwest mountains to the lower 60s in the Piedmont.
Forecast confidence is moderate for the Near term Period.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
As of 240 PM EST Thursday...
Pleasant Saturday then rain returns Sunday...
Upper closed low progged to lift NEWD from the southern Plains to
the Ohio Valley will allow for Gulf moisture advection along and
ahead of a translated sfc occluded front which will bring the
next increased chance for widespread rain showers to the area
for late Saturday night through Sunday. The good news is that
thermal profiles are quite warm and given such a SW approach
with the upper wave, it should be all liquid. Progged CAPE is
near nil so also not anticipation any thunder potential with
this system. QPF looks like a fairly quick shot of a third to a
half inch of rain for storm totals.
Forecast confidence is high.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 240 PM EST Thursday...
Mainly dry start to work week then precipitation chances increase
midweek with next system...
In the wake of the departing aforementioned upper low and sfc fropa,
a secondary weak shortwave and some enhanced deep layer moisture
quickly traverses the area Sunday into Monday morning, which could
linger some shower chances or at least some increased cloud
coverage. We shift then to a dry start of the work week with a
transition of zonal to SW flow aloft and some sfc ridging pushing
east. Overall active wave pattern continues as the next focus is on
an amplifying longwave trough and next approaching cold front to
bring another round of widespread precip to the area for Wednesday
and possibly into Thursday. There looks to be a sharp temp gradient
with this feature and cannot rule out perhaps a RA/SN transition
near the back side though may be too progressive to be an issue for
now and have plenty of time with this to monitor any guidance trends.
Temps overall look to be fairly cool and a bit below norm for early
in the week, then moderate to near or above normal Wednesday and
back even cooler for Thursday behind cold front.
Forecast confidence is medium.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
As of 715 PM EST Thursday...
Clouds were approaching the Mid Atlantic area from the south and
from the west. Bufkit forecast soundings show the atmosphere
saturating from the top down. Ceilings will lower through
12Z/7AM Friday. KBLF and KLWB will lower to MVFR by 14Z/10AM and
KBCB by 15Z/11AM. Areas to the east of the Blue Ridge will
remain VFR and KROA will be on the edge of the lower clouds.
Have kept KROA VFR for now.
A cold front crossing through the area of Friday will turn winds
to the west then northwest with a few hours of gusty wind behind
the front. Gusts up to 25 knots are likely in the mountains.
Once the front reaches central and eastern virginia and North
Carolina, downsloping wind will erode the clouds east of the
Blue Ridge. Expect KROA/KLYH and KDAN to all scatter out by
21Z/4PM.
Average confidence in ceiling, visibility and wind.
Average confidence in timing of rain.
Extended Aviation Discussion...
Clouds clear out in the mountains, becoming VFR Friday evening.
VFR conditions and dry weather continue through Saturday before
the next storm system brings rain and sub-VFR by Sunday.
Upslope low clouds are expected into Monday with a few
rain/snow showers around BLF/LWB possible. Sub-VFR could extend
as far east as ROA, with gusty winds. MVFR showers are possible
in the mountains Tuesday.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...KK/WP
NEAR TERM...AMS/KK
SHORT TERM...AB
LONG TERM...AB
AVIATION...AMS/KK