Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/23/18
Area Forecast Discussion
National Weather Service Denver/Boulder CO
859 PM MDT Tue May 22 2018
.UPDATE...
Issued at 853 PM MDT Tue May 22 2018
Convective focus shifting north and east and waning as the air
cools. The Denver area is sitting in cool outflow and while there
could still be some isolated weak showers, we should be done with
storms for the night. The main area of storms is shifting into
Wyoming. Still some potential near the eastern border overnight as
SSE winds will maintain dew points in the lower 50s. HRRR has been
overdoing convection out there, but it continues to show storms
moving north across the plains overnight. Our expectation is that
this potential will fade with cooling, but there remains some
chance most of the night. Lots of convective debris clouds at
present, but they should diminish over the mountains, with a
slower decrease on the plains as there is some upstream mid/high
cloudiness from stronger convection near the Colorado/New Mexico
border.
&&
.SHORT TERM...(This evening through Wednesday)
Issued at 322 PM MDT Tue May 22 2018
Radar and satellite data show scattered showers and thunderstorms
moving over the central mountains from south to north. Another
single storm is tracking toward southern Lincoln County from the
south. Storms are moving at a fair clip, so the threat of heavy
rain is reduced. Should see activity increase for a few more hours
and then dissipate after the sun goes down. Shower activity could
develop out over the I-25 corridor, but the rest of the plains
should remain dry this evening. Storms could also become strongest
as they reach the northern Colorado border, where deeper moisture
and instability are present.
For tomorrow, the upper low over the Great Basin is forecast to be
lifting northeastward while southwesterly flow aloft continues
across Colorado. Moist south to southeast flow are expected to
persist across eastern Colorado while the mountains also remain
under moist flow. Another round of afternoon showers is expected,
both over the mountains and out on the plains, where Gulf moisture
will be getting advected into the region. Storm Prediction Center
indicates that the eastern border of Colorado will be under a
marginal threat of severe weather. Temperatures will continue to
be slightly warmer than normal.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 322 PM MDT Tue May 22 2018
Wednesday evening`s convection and potential for a couple
strong/severe storms over the Nebraska border area will shift
north and east through the evening. Some of this may be driven by
a departing speed max to our north, so perhaps a couple storms
could linger til midnight or so before exiting over the far
northeast corner. Otherwise, look for a drying and stabilizing
airmass into Thursday as flow aloft turns more westerly. There`s
just a slight chance of a storm developing Thursday afternoon over
the far eastern plains along the edge of a dryline, but overall
PoPs will be quite low. Temperatures will continue their warming
trend Thursday, reaching the mid 80s across most of the plains,
with 60s and 70s in the mountains.
Summerlike weather will continue Friday and Saturday with a high
amplitude ridge building over the forecast area. In fact, by
Saturday we should see highs reaching or exceeding 90F across most
of the plains. The threat for afternoon and evening storms will
be lower through this period, although we still can`t rule out an
isolated storm or two over the mountains and eastern plains.
The focus will then shift toward the relatively deep upper level
low moving into the Great Basin/Desert Southwest late this
Memorial Day Weekend into early next week. This may bring a round
of active weather with an increasing severe weather threat as the
system approaches. At this time, we think the highest chance of
storms would hold off until Monday and Tuesday considering how
slow these high amplitude patterns typically progress. Time will
tell how much low level moisture can be pulled in ahead of this
system, but the overall pattern right now looks favorable for gulf
moisture intrusion and more active and potentially severe
thunderstorms at this time.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 853 PM MDT Tue May 22 2018
VFR through Wednesday. Winds should return to southerly at
KDEN/KAPA 04z-05z and remain southerly. Winds at KBJC should
become a lighter westerly by 06z. Only isolated thunderstorms
expected Wednesday afternoon.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Gimmestad
SHORT TERM...Dankers
LONG TERM...Barjenbruch
AVIATION...Gimmestad
Area Forecast Discussion
National Weather Service Boston/Norton MA
1004 PM EDT Tue May 22 2018
.SYNOPSIS...
On and off showers overnight ahead of a sweeping cold front. Mid
to late week warm, dry weather. Unsettled weather on tap for the
holiday weekend ahead of another sweeping cold front, however not
a washout.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
10 pm update...
Lingering showers overnight ahead of a sweeping cold front. Attendant
mid-level trof axis, vortmax energy pushing through. Secondary offshore
low sweeping by invigorated by ascent, the overnight show mainly forced,
just expecting scattered shower activity with convective energy absent
via blanket of clouds, earlier rains, subsequent cooler conditions.
Per SPC RAP mesoanalysis, absolutely no convective support.
Main concern is low clouds, fog. As prior forecaster noted, falling
temperature / dewpoint spreads, especially along the S-coast. HREF
probabilistically detailing dreary conditions along the high terrain
and S-coast. Light surface winds forecast. Leaning S-coast and waters
low visibility conditions, impact to motorists, mariners ...low beam
headlights advised. Some spotty locations across the interior, higher
confidence along high terrain. Dewpoints in the 50s, slightly humid
airmass, decent relative humidity. Low conditions now through roughly
6-7a Wednesday with sunrise.
Lows around the low 50s.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Wednesday...
A beautiful day is in store for the region as drier air works in behind
the weak cold front. Partly to mostly sunny skies should allow high
temperatures to reach the lower 80s in many locations away from
localized coastal sea breezes. While dry weather will dominate...a
shortwave and a local sea breeze boundary may be enough to trigger
a few brief late afternoon/early evening spot showers across eastern
MA.
Wednesday night...
If a few brief spot showers are able to develop across eastern MA...
they should dissipate after sunset. Otherwise, dry and tranquil weather
anticipated as a weak ridge of high pressure noses in from the west.
Overnight lows should bottom out in the upper 40s to middle 50s.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
Overview...
Broad mid level ridging continues across the northern tier
states into central Canada around 12Z Thursday as seen on 12Z
model suite and ensembles, which an H5 cutoff low sits off the
CA coast. The ridging does not last long, though, as H5 heights
signal a NW steering flow that gradually flattens out by the end
of the week. A mid level short wave and associated cold front
moves along in the flattening flow from southern Ontario late
this week into northern New England by the beginning of the
holiday weekend. Meanwhile, the western periphery of the
Bermuda high tries to extend toward the Carolina coast. Low
pressure in the Gulf of Mexico shifts slowly N while subtropical
moisture works N around the high across the southern
Appalachians. Limited moisture from the approaching front will
move south during Saturday, bringing scattered showers. May see
enough instability late Saturday into Sat evening to even see a
few thunderstorms.
The front becomes parallel to the mid level steering flow, so
it looks to stall near or just S of the region by Sunday. May
see a few weak waves move along this front, which will keep the
chance for showers through at least Saturday night. Some showers
may linger into Memorial Day mainly along S coastal areas.
Another short wave may approach sometime Tuesday with spotty
showers.
With H5 heights running in the 570-576 dm range late this week,
will see temps running well above seasonal normals especially
Friday and Saturday, then will fall back to near or a bit below
normal late this weekend into early next week.
Details...
Thursday through Saturday...
Large high pressure from the Great Lakes into New England will
bring dry but somewhat cool temps with sea breezes across
coastal areas. As the high moves offshore, winds shift to SW
and, as mid level heights rise, temps will as well Friday into
Saturday. Highs should run around 10 to 15 degrees above
seasonal levels away from the coast.
Clouds approach Friday night as cold front approaches from the
north. Will see chance for showers move into the Route 2 area by
late Sat morning. With the warm temps in place, along with
pretty good instability ahead of the front (SLIs around zero to
-1, K indices in the lower 30s and TQ values in the upper
teens), could see isolated thunderstorms develop.
Saturday night through Monday...
Cold front crosses the region Saturday night, with scattered
showers. Could also see isolated thunder Sat evening. Then, the
front will slow as it reaches the S coast Sunday. Some showers
will linger Sunday, then drier air moves in from Maine and N NH
as high pressure passes from Quebec into northern Maine during
Monday. Can not rule out some leftover showers especially along
the S coast during the day as the front lingers. Kept low chance
for showers mainly S of the Mass Pike.
Tuesday...
Still can`t rule out a few spotty showers at this point, but
lower confidence during this timeframe with wide model solution
spread.
&&
.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Short Term /through Wednesday Night/...High confidence.
Tonight...
CIGs/VSBYs lowering MVFR to IFR/LIFR. Lower S of MA-Pike and
along high terrain. Spotty interior low VSBYs, confined to
sheltered interior terminals, over high terrain with lower CIGs,
more widespread along immediate S-coast. Settling in 03-05z. SCT
SHRA activity overnight. Light S winds.
Wednesday...
Improving quickly 12-14z in all locations, latest Cape and Islands.
Breezy NW winds following, however an onshore flow along the coast
eroding with sunset. Isolated SHRA activity late afternoon into
evening, especially E/NE New England terminals with a more N wind-
shift.
Wednesday night...
VFR.
KBOS Terminal...
Potential sea-breeze around midday. NW winds becoming more S for
a brief period. Isolated SHRA possible around late afternoon
into evening. N wind shift behind SHRA activity into Wednesday
night.
KBDL Terminal...
Low CIGs overnight, likely to waver between MVFR-IFR through the
Wednesday morning push, quickly improving around 12z.
Outlook /Thursday through Sunday/...Moderate confidence.
Friday through Friday Night: VFR. Breezy.
Saturday: Mainly VFR, with areas MVFR possible. Breezy. Chance
SHRA, isolated TSRA.
Saturday Night: Mainly MVFR, with local IFR possible. Chance
SHRA, isolated TSRA.
Sunday: Mainly MVFR, with local IFR possible. Chance SHRA.
Sunday Night: Chance SHRA.
Memorial Day: Slight chance SHRA.
&&
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Short Term /through Wednesday Night/...High confidence.
Weak pressure gradient will keep winds and seas below small
craft advisory thresholds through Wednesday night. Showers this
evening. Main concern will be areas of fog overnight into part
of Wednesday morning...which may be locally dense especially
across our southern waters.
Outlook /Thursday through Sunday/...Moderate confidence.
Friday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Areas of seas approaching 5 ft.
Friday Night: Moderate risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of seas approaching 5 ft.
Saturday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Areas of seas approaching 5 ft. Slight chance of rain
showers.
Saturday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Chance of rain showers, isolated thunderstorms, patchy
fog. Areas of visibility 1 to 3 nm.
Sunday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain showers.
Sunday Night: Winds less than 25 kt. Areas of seas approaching
5 ft. Chance of rain showers, patchy fog. Local visibility 1 to
3 nm.
Memorial Day: Winds less than 25 kt. Seas locally approaching
5 ft. Slight chance of rain showers.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...None.
&&
$$
SYNOPSIS...Frank/EVT
NEAR TERM...Frank/Sipprell/EVT
SHORT TERM...Frank
LONG TERM...EVT
AVIATION...Frank/Sipprell/EVT
MARINE...Frank/EVT/GAF
Area Forecast Discussion
National Weather Service Buffalo NY
1053 PM EDT Tue May 22 2018
.SYNOPSIS...
Weak low pressure will track into northern New England tonight
with a few lingering showers and areas of fog tonight. High
pressure will bring a period of dry weather Wednesday through
Friday. Afternoon high temperatures in the 70s midweek will
steadily increase to the lower 80s for the start of the weekend.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
Weak low pressure across northern New York late this evening will
track into northern New England tonight. Any lingering showers
with a frontal boundary associated with this low will taper off
through midnight.
There are areas of fog across portions of Lake Erie and Lake
Ontario this evening. This fog is light across the majority of
the cwa, but webcams show locally dense fog near and south of
downtown Buffalo along the immediate Lake Erie shoreline. It is
a similar story east of Lake Ontario with areas of dense fog
there as well. A dense fog advisory is in effect for areas east
of Lake Erie and Lake Ontario. This fog will initially be
fairly localized near the lakeshores and enhanced by low level
convergence. However, this should become more widespread
overnight when low stratus are likely to lower in these areas.
This is depicted by the HRRR model. In addition to the advection
fog, there is a risk of radiation fog later tonight. The
concern here is that if there is any clearing as high pressure
builds in, this would be quickly followed by dense fog. If this
happens, the dense fog advisory may need to be expanded.
High pressure will ridge into the lower Great Lakes late
tonight, with drier air gradually building into the region. Lows
tonight will be in the lower to mid 50s.
High pressure will expand across the region on Wednesday. There will
be some lingering stratus and fog in the morning, but this should
gradually dissipate by afternoon. High temperatures will be mainly
in the 70s, except slightly cooler along the immediate lakeshore.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH SATURDAY NIGHT/...
The weather will be absolutely spectacular across the region for the
over whelming majority of this period...as a negatively tilted ridge
within a split flow will track across the Great Lakes region. The
ridge will deamplify with time though...and this will end up placing
our region between a slow moving back door cold front to the north
and the fringes of a large shield of tropical moisture to our south.
As we start the weekend...this will eventually bring an end to the
fine stretch of weather with showers and thunderstorms entering the
picture.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
Better agreement among Guidance packages with suppressing the
deeper subtropical moisture well south of the Lower Great Lakes.
Over the course of the Memorial day weekend look for
temperatures to nudge upwards (U70s-L80s)along with humidity
levels as deep southerly flow will transport some of the
available subtropical moisture to our south into our region. For
now, it looks like just increasing chances for showers and
thunderstorms during the day Sunday as the northern upstream
shortwave trough over Quebec Canada influences the Lower Great
Lakes. Monday into Tuesday, a cold front will cross the region
as the shortwave passes by to our north through Ontario Canada
with additional chances for showers and thunderstorms. Drier
weather with less humidity returns late Tuesday and Wednesday as
high pressure builds at the surface and aloft over New York
State.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
The main concern for aviation is areas of low stratus and the
potential for dense fog. The remains lots of low level moisture,
with low ceilings, especially east of the lakes where the the
moist air is mixing with the relatively cool lake waters. This
will result in mainly IFR conditions overnight, with areas of
dense fog. Another potential concern is if skies do clear out,
any clearing would quickly be followed by radiation fog.
Low moisture will gradually mix out Wednesday morning with
widespread VFR flight conditions by the afternoon.
Outlook...
Wednesday night through Friday...VFR.
Saturday...Mainly VFR. A chance of showers.
Sunday...MVFR. Showers likely.
&&
.MARINE...
Winds will not be very strong, however there will be areas of
fog due to the warm moist air across the relatively cool lake
waters. Surface high pressure will near the region Wednesday,
passing over the Eastern Great Lakes Thursday, before shifting
towards the Southeast states on Friday. This will maintain light
winds and minimal waves through the end of the week.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Dense Fog Advisory until 8 AM EDT Wednesday for NYZ006>008-010-
019-020-085.
MARINE...None.
&&
$$
SYNOPSIS...Apffel
NEAR TERM...Apffel
SHORT TERM...RSH
LONG TERM...AR
AVIATION...Apffel
MARINE...Apffel
Area Forecast Discussion
National Weather Service Sioux Falls SD
1034 PM CDT Tue May 22 2018
.SHORT TERM...(This evening through Wednesday)
Issued at 321 PM CDT Tue May 22 2018
The primary concern over the next 24 h is the potential for heavy
rainfall overnight and the lower probability of severe weather this
evening and overnight.
At 18Z this afternoon, the surface warm front extended across
northern Nebraska from north of ODX to south of OFK. This front is
slowly expected to lift north into the evening. Both the 17Z HRRR
and 17Z RAP have recently begun to show convection developing this
afternoon. This seems to be an model initiation issue as current
satellite does not show any indication of thunderstorm development
through 21Z. The only area of concern in the late afternoon and
early evening is the area of stratocumulus along and south of the
Missouri River. At this point, there is no sign of storm
development but if temperatures can warm into the low 80s with dew
points in the upper 60s, that could allow an isolated storm to break
the cap. With 0-3 km helicity over 250 m2/s2 and CAPE over 2000
J/kg, any storms that form near the Mo River prior to sunset could
become severe. However, the probability of any surface-based
development is low and would remain isolated.
The greater concern is toward sunset. A weak upper level wave will
be moving north into northern Nebraska at that time. With low level
frontogenesis, MUCAPE of 1000-2000 J/kg and CIN < 25 J/kg, expect
storms to develop in the vicinity of I-90 within an hour or two of
sunset. Since these storms will be a little elevated, shear is only
30 kts meaning that storm mode is most likely to be multicellular.
Initial updrafts which have access to the best instability may be
able to produce quarter size hail but that threat should only last a
couple of hours - perhaps as late as 06Z. A second wave will then
move into eastern South Dakota after 06Z. This approaching wave will
cause the low level jet to increase across Nebraska which will lead
to both enhanced moisture transport over the surface boundary and
increased convergence at the nose of the jet near I-90. Agree with
hi-res model solutions which show a significant increase in storm
coverage near or north of I90 after midnight. As storms grow upscale
a cold pool is expected develop and is likely to impede the
northward movement of the front. Corfidi vectors also show that the
MCS will have a slow movement to the east southeast. This will allow
for some areas to get 1 to 2 inches of rain overnight - with locally
higher amounts possible. Based upon the expected location of the low
level front and jet, the most likely area for heavy rain looks to be
from north of Sioux Falls to the Iowa and Minnesota border. However,
this axis could shift north if storms develop later in the night
allowing the front to move closer to Highway 14. Because Flash Flood
Guidance is around 2" in 3 h and the location of heavy rain is
somewhat uncertain, have not issued a Flash Flood Watch for tonight.
However, with brief periods of 1-2"/h rainfall rates possible,
ponding of water in urban and poor drainage areas could occur.
Storms are expected to exit to the east by late Wednesday morning.
With skies becoming most clear, rising mid level height and warming
temperatures above 700 mb, additional storms are not expected to
redevelop Wednesday afternoon. With at least partly sunny skies and
southerly flow, temperatures will be in the 80s with 90 degrees
possible west of the James River. Dew points will be in the mid 60s
so it will also feel humid.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 321 PM CDT Tue May 22 2018
On Wednesday night, there is a strong shortwave that moves from
western Wyoming into eastern Montana. There are a series of short
waves further to the south and east, but the main wave is located
across the far west. Winds increase out of the south, but the nose
of the low level jet appears to be focused to the north across North
Dakota. Portions of central South Dakota may be brushed by short
waves lifting to the northeast. Therefore, have some slight chance -
low end chance pops west of the James River Valley.
More significant chances of storms are expected on Thursday as a
short wave train moves across the area from southwest to northeast.
Have increasing speed shear with height, but increase is meager with
very little directional shear. This once again results in 0-6km
bulk shear of 20-25 knots. With that said, surface based CAPE
values of 2500-3000 J/kg may allow for isolated severe mainly for
hail and wind.
On Friday into next week, upper ridge develops across the Western
Plains leading to relatively dry conditions. With the Gulf wide
open and southerly flow continuing, should see prolonged warm and
humid conditions. Have nudged temperatures upwards through the
weekend into next week, but not as much as the warm GFS would
suggest. Looks to be a quick transition to summer like conditions.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1027 PM CDT Tue May 22 2018
Around the first 6 hours of the TAF period look to have the most
impacts at HON and FSD with showers and thunderstorms possible.
With convection mostly failing to break out this evening, have
backed off on thunder at FSD and left a couple hours of VCTS when
thunder would be most likely. Other than the potential for showers
and thunder, only other thing to look out for would be gusty winds
Wednesday afternoon across the region. Could see a few mid level
cumulus clouds at or around 4 kft as things mix out.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.
&&
$$
SHORT TERM...Schumacher
LONG TERM...BT
AVIATION...Ferguson
Area Forecast Discussion
National Weather Service Hastings NE
648 PM CDT Tue May 22 2018
.SHORT TERM...(This evening through Wednesday)
Issued at 332 PM CDT Tue May 22 2018
Temperatures this afternoon have reached into the mid 80s to low
90s across the area. Tonight overnight lows in the mid 60s are
expected with a chance of showers and thunderstorms moving across
the region. The NAM and GFS and the higher-resolution RUC/HRRR
indicate the chance for showers and thunderstorms to develop this
evening in northwest/north central Kansas and track northeast
across the forecast area overnight exiting into north
central/northeast Nebraska by morning. Shear is not overwhelming,
but there is 1000-1500 J/kg CAPE for thunderstorms.
During the day Wednesday, some of the guidance indicates a chance
for showers and thunderstorms extending into the morning hours,
however, expect most of the day to be dry across the area.
Temperatures will be similar to today across the region with highs
in the mid to upper 80s.
The western half of the area remains in a SPC Marginal Risk for
Wednesday, but question how far any activity will make it and have
kept a nearly dry forecast. Feel best chance for thunderstorms
will be west of the area.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 332 PM CDT Tue May 22 2018
The main take away for this period is that it will be hot, well
above normal for this time of year. High temperatures through the
end of the weekend look to be in the upper 80s to low 90s as the
main upper trough stays out to the west and ridging sets in over
the central Plains.
The best chance for precipitation will be Thursday night into
Friday morning ahead of the warmest temperatures for the weekend.
A disturbance will approach the area during the day Thursday with
storms developing and an MCS moving across Nebraska through the
overnight hours.
The beginning of the work week cools down some (but not a lot) as
the upper low finally moves east far enough to impact the area.
There will be some additional chances for precipitation as this
low moves towards the area, but it is too early for details.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Wednesday)
Issued at 644 PM CDT Tue May 22 2018
Significant weather: LLWS at both TAF sites tonight
Tonight: Diurnal CU field will dissipate within the next 1-2 hrs.
Expect LLWS to dvlp at EAR by around 06Z and GRI by around 07Z w/
strong SSWrly LLJ of 40-45kts expected. Think HRRR is overdone
with convection this eve and have kept TAFs dry as activity should
remain W of the terminals.
Wednesday: LLWS should weaken just after sunrise. Expect a CU
field to dvlp once again as convective temps are met near or just
after midday. Winds will become brzy out of the S as well, w/
gusts up to 24kts during the aftn.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&
$$
SHORT TERM...Billings Wright
LONG TERM...Billings Wright
AVIATION...Thies
Area Forecast Discussion
National Weather Service Wilmington NC
918 PM EDT Tue May 22 2018
.SYNOPSIS...
A tropical airmass will remain across the Carolinas for the next
week. A cold front approaching from the north will become a
focus for better chances of showers or thunderstorms during
Wednesday and Thursday. The front will dissipate Friday, with
fewer showers expected into Saturday. Low pressure developing
this weekend across the Gulf of Mexico will throw more moisture
our way for Sunday and Monday, with substantial rain chances
returning to the area.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
As of 830 PM Tuesday...Diurnally driven convection has ended
across the ILM CWA. The 88D echoes over the adjacent Atlantic
waters are for the most part chaff. Will update to remove POPs
for the rest of this evening. Based on latest Sat imagery
trends, have improved sky conditions by cutting back on the
clouds for the remainder of this evening and into the pre-dawn
Wed hrs. This could set up a night for patchy to possibly areas
of fog if the sfc winds are able to decouple. Local PWS at 1.2
this morning will rise to around 1.7 Wed morning. During the
pre-dawn Wed hrs, have indicated a low chance POP, mainly along
the immediate coast and waters and stretching inland by 25
miles. This the result of a weak system traversing northeast
across the coastal area as it tracks northeastward...reaching
the NE portions of the CWA around daybreak Wed. Have
tweaked the hrly temps/dewpts and tonights lows, but with no
categorical changes.
Previous......................................................
As of 300 PM Tuesday...The convection that developed along
the sea- breeze just before noon is now decreasing in coverage.
Inland isolated convection appears to continue as the HRRR 16
UTC is not showing an increase activity this evening. So will
continue with isolated showers and thunderstorm through the
evening.
At the surface the area will continue to be on the eastern
edge of the Bermuda high and the deeper moisture is seen
returning with precipitable water near 2 inches. Both the NAM
and GFS are showing diurnal convection with the GFS being a bit
more zealous with convection in the northwest quarter of the
area. The NAM is showing less precipitation mainly west of the
sea- breeze and focused over northeast South Carolina. The 12
UTC ECMWF is closer to the NAM12 solution.
Lows tonight will range from the upper 60s inland to the
lower 70s at the coast. Highs on Wednesday will be in the
middle 80s inland and the lower 80s at the coast.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 300 PM Tuesday...The chance for showers and
thunderstorms will increase Wednesday night into Thursday as a
cold front drifts south across the forecast area. The
precipitable water will pool ahead and along the boundary along
with marginal to moderate surface based instability. While the
amount of cloud cover will ultimately impact the amount of
instability any increase in cloud cover would also imply
slightly cooler temperatures than what is currently forecast.
For now favor a blend of MAV/MET temperatures, and POPs
decreasing Thursday evening with the front drifting farther
south and dissipating.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 300 PM Tuesday...A baggy upper level trough across the
lower Mississippi Valley and Gulf of Mexico will become better
defined Saturday and Sunday. Upper ridges building across the
Pacific coast of Mexico and out over the western Atlantic
between the Bahamas and Bermuda will help to spin this feature
up. A surge of Caribbean moisture very similar to what we saw
last weekend will be drawn northward in the deep southerly flow
between this upper trough and the offshore ridge, and this
could lead to another good rainfall event Sunday into Monday.
The latest WPC QPF outlook for just Sunday and Monday is around
1.5 inches across our area, with forecast 7-day totals of 2-3
inches.
Latest models show there will probably be some sort of low
pressure development across the Gulf of Mexico late this week,
but FSU cyclone phase diagrams show only the Canadian
developing a significant warm core aloft. The 12z ECMWF (not
currently part of the FSU website) shows the cyclone keeping a
pronounced gradient in 1000-500 mb thickness above the surface
low, implying subtropical characteristics at best. The GFS is
the farthest east with its low pressure development across
Florida on Sunday, while other guidance is westward. While not
ruling out anything just yet, it`s expected the low will remain
too far west for any direct impacts on the Carolinas, but
enhanced southerly flow should help enhance our rainfall
potential Sunday and Monday when my highest rainfall chances
(50-70 percent) are currently forecast.
The warmest days should be Friday and Saturday when there will
be more sunshine and lower shower chances. Highs should reach
the mid to upper 80s both days inland, several degrees cooler
near the coast. Temperatures should top out in the lower 80s
Sunday, and lower to mid 80s Monday and Tuesday. Lows in the
upper 60s to lower 70s through the period are evidence of the
tropical airmass we`ll have in place.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
As of 00Z...VFR through the evening hours with a moderate
south southwest flow. Overnight, could see some IFR conditions,
mainly with respect to ceilings. Visibilities will be MVFR as
some mid cloud ceilings above the stratus will hinder fog
formation. Wednesday, time height indicates fairly good moisture
through 500 mbs. The LFC should be fairly low and convection
should kick off around noon, with more coverage than today.
Extended Outlook...The potential for MVFR/tempo IFR will
increase late Wed/Thur as a cold front drops across the area
and again during the weekend as tropical moisture returns.
&&
.MARINE...
NEAR TERM /THROUGH WEDNESDAY/...
As of 845 PM Tuesday...Latest 88D echoes over the local waters
are NOT showers or thunderstorms, they mimic aluminum chaff
used by the military to evade radar tracking. Do think, showers
and convection will occur, mainly during the pre-dawn Wed hrs as
a weak system moves northeast along the immediate coast.
The sfc ridge axis from Bermuda high pressure, will continue to
extend west and onshore. This onshore placement is now south of
the local waters. This has resulted with mainly a SW direction
for all waters. The sfc pg will be conducive to around 10 kt or
10-15 kt wind speeds. Significant seas will run around 3 ft and
will primarily be influenced by the SE ground swell that has
shown some degradation during the past 12 hrs.
Previous...................................................
As of 300 PM Tuesday...The marine waters will continue to be
under the influence of the high pressure we have seen the last
few days. Winds will be southwest overnight and will shift to
the south on Wednesday as the sea-breeze develops. Winds will be
around 10 knots increasing to 10 to 15 knots during Wednesday.
Seas will range between 2 and 3 feet through the period.
SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 300 PM Tuesday...Bermuda high pressure will maintain
southwesterly flow across the waters Wednesday evening. However,
the flow will veer to a westerly direction as a weak front
drifts south across the area. The front is expected to become
increasingly diffuse as it passes south of the waters allowing
weak onshore flow to prevail by Thursday afternoon. Seas will
be 3 ft or less through the period. Scattered showers and
thunderstorms are also possible with the front in the vicinity.
LONG TERM /FRIDAY THROUGH SUNDAY/...
As of 300 PM Tuesday...Bermuda high pressure will remain well
off the Southeast coast this weekend. By itself it would provide
a gentle southerly wind and typical summertime weather. However
models over the past few days have been showing the potential
for a tropical or subtropical cyclone to develop across the
Gulf of Mexico Friday or Saturday. The GFS is the farthest east
of any model with its latest run showing a low reaching Florida
on Sunday, while the ECMWF and Canadian are farther west. While
it`s too early to completely rule out impacts, our latest
forecast has south winds increasing to around 15 kt Sunday, with
a lengthening fetch of stronger winds extending down into the
Bahamas. This could build seas up toward 6 feet, assuming our
wind forecast is correct.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.
&&
$$
SYNOPSIS...TRA
NEAR TERM...DCH/DRH
SHORT TERM...SRP
LONG TERM...TRA
AVIATION...DL
Area Forecast Discussion
National Weather Service Nashville TN
849 PM CDT Tue May 22 2018
.UPDATE...
FOR EVENING DISCUSSION.
&&
.DISCUSSION...
Earlier showers and storms have almost entirely dissipated as a
weak surface boundary makes its way through Middle Tennessee.
The boundary layer remains nearly saturated even behind the front,
so we`re leaving in patchy fog during the overnight period. Have
reduced POP`s to just 20% across eastern parts of the mid state
for the next couple of hours. HRRR shows no redevelopment
overnight, so we`ll let the POP`s drop off after 11 p.m.
&&
.AVIATION...
00Z TAF DISCUSSION.
BNA/MQY/CKV/CSV...A weak surface boundary is working its way
across Middle Tennessee this evening just as a line of storms
moves through the Nashville metro area. Storms should be south of
the BNA & MQY terminals by 01Z. Afterwards, look for drier air to
begin filtering into Middle Tennessee. Expect some radiation fog
overnight, with very little chance of convection on Wednesday.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION......08
AVIATION........08
Area Forecast Discussion
National Weather Service Pocatello ID
220 PM MDT Tue May 22 2018
.SHORT TERM...Tonight through Friday afternoon. The low
pressure disturbance moving up from southern Nevada is taking it`s
time, drifting a little east and northeast. Water vapor imagery
seems to show the center a little closer to the Utah border than any
of the models. The latest run of the RAP looks closer in agreement
with satellite. Suspect it will drift northeast into Montana as
models generally want it to on Wednesday. In the meantime, this
makes it difficult to place and time thunderstorms. The South
Central and Caribou Highlands will probably see a few thunderstorms
yet this afternoon and evening, it will just take a couple or three
hours. A few cells have developed between Rexburg and Driggs,
expected to move west towards Arco this evening. Still forecasting
scattered to numerous showers in the Upper snake Highlands Wednesday
morning. The low off shore is still dropping south and should help
increase the amplitude of ridging over the Great Basin by Thursday
to allow warm air moving north to Idaho. RS
.LONG TERM...Fri night through next Tue night. 500mb long wave
forecast for this time breaks into two distinct patterns. The early
set up is to continue with the trough along 140E longitude, keeping
southwest flow with potential interacting with subtropical moisture
for continue thunderstorm activity with mild temperatures. By Mon
morning, this Pacific trough-Great plains ridge de-amplifies and
becomes zonal by Mon afternoon. This just puts a lot of uncertainty
into the forecast. The storm track is pushed into central and
northern Canada. The only certainties for any day in this period is
that temperatures should be above normal for the time of year,
likely both highs and lows; and, with no strong upper level flow
likely, wind should continue to be light. Both the ECMWF and GFS
bring a closed low into Great Basin, with the GFS low coming in
farther south. Both scenarios though bring showers and thunderstorms
slowly through the Basin, first in the western zones Fri night/Sat
morning, then the entire forecast area by Sat afternoon and evening.
The precipitation is even heavier for Sat late night through Sun
evening as the low continues to move very slowly. After midnight
Sun, the guidance suites start to diverge more strongly in solution,
with the ECMWF developing an upper level low in central Montana,
while both keep the main low in either Utah or Arizona. So on
Memorial Day itself, the afternoon will continue to be stormy,
with the main focus of convection in the central Idaho mountains.
By Tue morning, there is some let-up in precipitation production
as the main closed low finally slides east of Idaho latitudes, to
the Utah- Colorado border region-but it is only a decrease, not an
elimination. Messick
&&
.AVIATION...Light SHRA have already developed and are moving from
southeast to northwest through the area. HRRR indicates a line of
TSRA moving into the three low elevation airdromes (KBYI,KPIH, and
KIDA) sometime around 22/21Z and 22/22Z, with relatively high
probability of TSRA during the period, so have attempted to time
this line and have inserted TEMPO groups. KSUN is expected to have
this threat for the longest time and a little bit later, and so the
TEMPO group for this airport lasts a little longer. Lowest threat
for TSRA is KDIJ (but it`s not zero). After midnight the moisture
really moves into the Teton Valley and expecting marginal VFR by
morning with some moderate to heavy precipitation. The threat of
SHRA and TSRA should be even greater on Wed afternoon. KDIJ may not
break out of the low CIGs on Wed. Messick
&&
.PIH WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Area Forecast Discussion
National Weather Service Pueblo CO
317 PM MDT Tue May 22 2018
.SHORT TERM...(This evening through Wednesday)
Issued at 317 PM MDT Tue May 22 2018
...Critical Fire Weather Conditions expected across the San Luis
Valley Wednesday...
Isolated thunderstorms will continue to develop across the area
through this evening though coverage has been more sparse than past
couple days. HRRR continues to advertise a line of showers and
thunderstorms developing down around Walsenburg and expanding and
moving northeastward towards Fowler along convergent boundary within
surface trof axis through the late afternoon. Main threat with
thunderstorms through the evening will be plentiful amounts of small
hail and wind gusts to around 50 mph, as it is supported by around
1000 j/kg of CAPE but deep layer shears more in the 20-30 kt range.
This activity lifts off to the northeast with some redevelopment
across the southern border counties of the southeast plains during
the overnight hours. Some iterations of the high res models keep
this activity to the south...across the New Mexico/Ok Panhandle
region. But with some lift possible due to strengthening low level
jet have opted to maintain some isolated pops out that way.
Otherwise...convection over the mountains should decrease during the
evening hours and diminish for most areas by midnight.
Western U.S upper low opens up and lifts out on Wednesday with main
circulation center lifting northeastward into the northern U.S.
Rockies. Main effect for our area will be a warming and drying
trend as a dry air mass helps to knock back dew points across the
mountains and valleys. Given increasing flow aloft, winds in
soundings look sufficiently strong to support a Red Flag Warning for
the San Luis Valley where RHs are expected to drop low enough for
long enough to meet the 3 hour duration. Across the plains, dryline
will be mixing eastward during the afternoon with northern portions
of the I-25 corridor across El Paso and Pueblo counties and
potentially portions of Crowley and Otero counties seeing dew points
fall into the upper 20s and 30s. Could see an hour or two of
critical fire weather conditions for these areas as well, but not
quite getting the areal coverage and duration of RH below 15 percent
to justify a Red Flag Warning. To the east of the dryline, CAPE
values will be running in the 1000-1500 j/kg range. Unidirectional
nature of the winds are not yielding very high deep layer shear
values though, so threat for widespread severe looks limited. With
decent CAPE however, can`t rule out a marginal near severe storm or
two across the plains. Will maintain isolated pops across the
eastern counties. Main threat would be gusty winds and hail. -KT
.LONG TERM...(Wednesday night through Tuesday)
Issued at 317 PM MDT Tue May 22 2018
Wednesday night-Thursday...Southwest flow aloft across the region
Wednesday afternoon moderates Wednesday night and becomes more
westerly through the day Thursday, as a broad upper trough
translates north and west across the Northern Rockies and upper
level ridging builds into the Great Basin. Models still hinting at
the potential for a few stronger storms along a dryline across the
far Southeast Plains and western Kansas border late Wednesday
afternoon with the potential continuing through the evening with
models developing a low level jet along the Kansas border. Drier and
warmer air within the westerly flow aloft will help to keep
convection at bay on Thursday, however, still can`t rule out an
isolated high based late afternoon storm over the higher terrain and
possible across the far Southeast Plains, where best low level
moisture resides. Temperatures on Thursday look to remain above
seasonal levels, with highs in the 80s to lower 90s expected across
the lower elevations, 60s and 70s across the higher terrain and 40
and 50s at the peaks.
Friday-Saturday...Upper level ridging builds across the Rockies into
the early part of the holiday weekend, as Eastern Pacific energy
digs across the West Coast and into the Great Basin. Pattern
supports warm and mainly dry weather, with temperatures expected to
remain above late spring norms, as highs warm into the mid 80s to
mid 90s across the lower elevations, and mainly in the 60s and 70s
across the higher terrain. As for precipitation, can`t totally rule
out some high based convection in the afternoon and early evening
hours over the higher terrain, though soundings support mainly virga
and gusty winds.
Sunday-Tuesday...Models fairly consistent of increasing southwest
flow aloft across the region as developing upper low across the
Great Basin slowly weakens as it ejects north and west across the
Northern Rockies through early next week. Again, pattern would
suggest mainly dry, warm and breezy conditions across the area with
increasing fire danger and the potential for critical fire weather
conditions across portions of the South Central and Southeast
Colorado, along with the potential for strong to severe convection
across the far Southeast Plains into early next week with possible
dryline interaction.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 317 PM MDT Tue May 22 2018
Isolated thunderstorms will develop across the area through this
evening, producing VFR cigs/vis along with the potential for some
small hail, and erratic gusty winds up to 45 kts. Likelihood of
these impacting the terminals is small, with KALS and KPUB seeing
the best chance for VCTS and erratic gusty winds. Otherwise,
activity will diminish this evening with clearing skies. KALS could
see a return of patchy ground overnight which could result in IFR to
LIFR conditions for a 3 hour window around/shortly after sunrise.
Otherwise, TAF sites will see increasing southwest winds on
Wednesday with gusts in the 25-30 kt range. Thunderstorms will be
less likely for the TAF sites as drier and warmer air works in. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from noon to 8 PM MDT Wednesday for COZ224.
&&
$$
SHORT TERM...KT
LONG TERM...MW
AVIATION...KT
Area Forecast Discussion
National Weather Service Raleigh NC
911 PM EDT Tue May 22 2018
.SYNOPSIS...
A lee trough will linger over the srn middle Atlantic states ahead
of a cold front that will settle southeastward into the area late
Wednesday and early Wednesday night. Following high pressure will
ridge south across the region on Thursday.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 900 PM Tuesday...
A mid/upper level trough will approach from the west tonight,
allowing for a weakening band of showers and isolated thunderstorms
to move into western/northern portions of the area late this
evening/early Wednesday morning. However, the latest HRRR has
trended towards very little of this activity making it into central
NC. Given nocturnal stabilization and PW`s noticeably lower tonight,
with the KGSO sounding showing PW`s of only 1.21 inches this
evening, will lower pops some and only keep a low end chance across
the far west and north late this evening into early Wednesday
morning with a slight chance elsewhere. Low temps temps will remain
warm though for this time of year, generally 65-70 degrees.
&&
.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
As of 345 PM Tuesday...
At the base of a mid-upr low migrating ewd across Hudson Bay and
Quebec, a series of minor perturbations will sweep across the
Northeast and middle Atlantic Wed, then offshore by Wed night. Mid-
upr lvl flow will consequently strengthen slightly and veer to nwly
over cntl NC, with effective bulk shear values likely to increase
into the 25-30 kt range.
At the surface, a cold front will settle swd, in backdoor fashion,
across VA during the day, then into the nrn NC Piedmont very late
Wed afternoon and evening, where it will overtake a preceding, quasi-
stationary lee trough over w-cntl NC. The front, modulated by
convective outflow, will settle swd through cntl NC overnight. A
somewhat drier/lee humid/cooler air mass will follow, as post-
frontal high pressure ridges swd across the middle Atlantic region.
Initially scattered showers and storms are likely to focus along
remnant outflow from convection from the previous day/night; and
also along the lee trough. This activity is expected to become
numerous by late afternoon and early evening, as convergence/lift
increase with the arrival of the surface front. Storms are likely to
become semi-organized in a multi-cellular storm mode along common
outflow, with an associated strong to isolated damaging wind threat
as storm clusters propagate sewd, with the relative greatest
potential where the aforementioned bulk shear should be maximized
over the nrn Piedmont and nrn Coastal Plain.
The chance of showers and storms will linger overnight, particularly
over the srn half of the CWFA, as the (effective) frontal zone
settles swd. Any earlier severe threat will have diminished owing to
both nocturnal cooling and prior convective overturning.
Generally persistence temperatures in the mid-upr 80s are expected
on average, though modulated and shortened by convection/clouds,
with lows in the mid 60s to around 70 degrees.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
As of 235 PM Tuesday...
Progressive high pressure over the Great Lakes will make a stab at
drying us out, pushing a front south of the area early on Thursday.
With the front along or south of the area, will have only small
chance PoPs along the southern tier counties Thursday into Thursday
night. Highs will be only mildly influenced by the front due to
strong insolation and should reach mostly mid 80s.
The high moves off the New England coast, with return flow beginning
to spread into the west Friday into Saturday. As such, chance
category PoPs in the west Friday taper off eastward, with all areas
in the low chance category on Saturday as we sit beneath an upper
ridge conducive to airmass thunderstorms in the resulting unstable,
but weakly forced environment. Highs both days will mostly reach mid
80s after mild morning lows in the mid and upper 60s.
The moisture transport from the south returns once again for the
late weekend aided by the Bermuda high and a developing low pressure
system in the Gulf of Mexico. The moisture return will increase
precip coverage Sunday and into early next week, and while there is
a lot of uncertainty as to the timing of forcing mechanisms driving
heavier convection, it will be diurnally influenced, and will
maintain high chance to likely PoPs Sunday through Tuesday. Highs
will show little variation from previous days, mostly mid 80s, with
morning mins in the soupier airmass closer to 70 each morning.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
As of 720 PM Tuesday...
Showers and storms, other than a few extremely localized downpours,
have cleared central North Carolina by late evening Monday. Additional
showers may be possible near to slightly after dark at INT and GSO,
primarily related to the approach of a mid level trough and band of
upstream convection now over the central Appalachians. Storm
coverage is otherwise expected to remain isolated and/or of limited
with decreasing coverage as the night continues. Similar to Tue
morning, IFR-MVFR ceilings will be possible in the several hours
centered around 12Z, with rising CIGs and eventually shower and
thunderstorm development by Wednesday afternoon/evening.
Outlook: Otherwise, another round of sub-VFR ceilings will probably
result late Wed night-early Thu, owing to low level moisture
convergence along and ahead of the aforementioned frontal zone.
After relatively dry/VFR conditions Thu-Sat, moisture will increase
by Sun-Mon, with resultant increasing probabilities of convection
and morning stratus and/or fog during that time.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...MWS
NEAR TERM...BSD
SHORT TERM...MWS
LONG TERM...mlm
AVIATION...JJM/MWS
Area Forecast Discussion
National Weather Service Blacksburg VA
1137 PM EDT Tue May 22 2018
.SYNOPSIS...
A weak cold front will approach from the northwest tonight
before sliding through the region on Wednesday. High pressure
noses down from the Ohio Valley and Mid Atlantic Wednesday night
into Thursday, then off the coast by Friday.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
As of 1135 PM EDT Tuesday...
Based on current radar trends and a blend of Hi-Res guidance
with HRRR have lowered probability of precipitation for the rest
of the night across much of southwest Virginia and northern
North Carolina. Only minor changes needed to overnight lows.
Still expect the surface cold front which extended from
Pittsburgh to Cape Girardeau to bring a chance of showers into
southeast West Virginia, mainly after 08Z/4AM.
Surface cold front sags through the region from the north/northwest
Wednesday preceded by deepening northwest flow in the wake of the pre-
frontal boundary from this evening. Guidance showing this trajectory to
allow some drying aloft with PWATs dropping off in all except the far
southeast where the boundary will likely end up by late in the day.
This looks to be the region for added deeper convection Wednesday
afternoon as a tight forecast instability/theta-e gradient exists.
However the majority of the stronger cells may end up just south of the
area as suggested by the Nam/GFS with more isolated coverage farther
north. Highs mostly low/mid 80s east and 75-80 west pending clouds far
west and strength of downslope out east.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
As of 300 PM EDT Tuesday...
Our forecast pattern will be transitioning into a relatively brief
drier period during this portion of the forecast. An upper level
ridge is expected to become parked over the mid-Atlantic region.
This will help shunt moisture southwest of our region along with
most of the cloud cover. Temperatures will also tend slightly
cooler, mainly the result of lower dew points allowing for slightly
cooler low temperatures.
The exception to the above rule will be Wednesday night in the
southeast where there will be some lingering precipitation
associated with a departing cold front. Also, the Northern Mountains
of North Carolina may be far enough southwest of the center of the
ridge axis to have a bit of a moisture return that will allow for
some afternoon diurnal showers Thursday. On Friday a slightly larger
part of the southwest portion of the area may see some of these
showers, and a few thunderstorms, as the center of the upper ridge
shifts a bit east.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 330 PM EDT Tuesday...
This portion of the forecast period will be one characterized by a
generous return of moisture to the area. The upper ridge over the
mid-Atlantic will head southeast and become centered in the western
Atlantic, east of GA/FL. This will again open the door for Atlantic
and Gulf of Mexico moisture to stream into the region. Northern
stream energy will again progress into or just north of the region
along a baroclinic zone, allowing for coverage of showers and storms
similar those those of recent days. We even may be influenced by
moisture heading north from what may be a tropical system in the
east Gulf of Mexico by early next week.
Temperatures during this portion of the forecast will average five
to ten degrees above normal.
&&
.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
As of 1245 PM EDT Tuesday...
Clusters of showers and storms developing across the western
mountains will shift slowly east reaching the Blue Ridge by
19-20Z/3-4PM, and eastern locations between 20-23Z/4-7PM.
Will likely see more of a scattered coverage west to start with
most Taf sites having at least thunder in the vicinity but will
likely include a Tempo period of thunder from northwest to
southeast into this evening. Potential to see at least a broken
line along and east of the Blue Ridge later this afternoon so
boosting thunder mention east later on.
Looks like activity wanes in the evening with some clearing
taking place to allow for fog, dense at times to form. Should
see at least MVFR fog to IFR stratus at most sites, with dense
fog at KLWB/KBCB late.
Appears any low clouds/fog will fade by mid morning Wednesday
leading to more in the way of VFR across the region through
early afternoon. Added sub-VFR conditions will be possible
mainly southeast of a line from KLYH- KDAN with most activity
likely south of the region later in the afternoon.
.Extended Aviation Discussion...
Conditions are will be drier and are expected to be VFR
Thursday and Friday. Tropical like moisture streams back north
as a warm front moves through Saturday with a return to
showers/storms and potential sub-VFR conditions and heavy rain
by Saturday afternoon/evening.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...JH/WP
NEAR TERM...AMS/JH
SHORT TERM...DS
LONG TERM...DS
AVIATION...AMS/JH/RCS/WP