Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/05/21
AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
857 PM EDT Sun Jul 4 2021
.SYNOPSIS...
High pressure will linger over the area through tonight. The
surface high slides offshore late Monday and Tuesday, allowing
warmer, more humid airmass to gradually return Monday through
midweek.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
As of 850 PM EDT Sunday...
Latest analysis reveals a weakening/diffuse sfc trough just to
the W/NW of the local area. Farther west, 1016+mb sfc high
pressure continues to build across the region from the OH/TN
River Valleys. Aloft, closed low continues to slowly lift E/NE
across eastern New England into Atlantic Canada, with the upper
trough axis extending S/SW across the northeast and Mid-
Atlantic coast.
Time-lagged HRRR and majority of CAMs showing some isolated
showers across the Blue Ridge, aided by one last spoke of
shortwave energy pivoting around the upper low and dropping
SE across the area overnight. This will most likely result in
some increasing mid to high clouds overnight over the northern
half of the area. However, a slight chc PoP (AOB 20%) has been
maintained for after 03z/11p into the overnight hours. PW values
are near or just below climo and not expecting much more than a
spotty stray sprinkle or two near and just after midnight.
Otherwise, dew points will begin to creep up slightly late as
the return flow develops. This along with the clouds will keep
lows in the low- mid 60s, though some upper 50s possible over
interior south central VA and NE NC with better radiating
conditions.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
As of 230 PM EDT Sunday...
The gradual warming continues with the warmest temps expected
Tuesday and Wednesday. Temps at 850mb are forecast to increase to 17
to 18C on Monday to 19C to 20C on Tuesday/Wednesday. Should see
plenty of upper 80s/lower 90s on Monday with low to mid 90s Tue/Wed.
Lee trough sets up especially on Tuesday, but it will simply be
too dry in the column for any shower/storm activity. Any
thunderstorm activity will need to wait until Wednesday when
some deeper moisture tries to stream northward on the back side
side of the ridge. However, even on Wednesday PoPs will
generally be slight chance or low chance.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 230 PM EDT Sunday...
The first part of the extended still depends on the track of Elsa as
it moves near the Middle Atlantic Thursday. Latest guidance from NHC
suggests whatever is left of Elsa will move over the Middle Atlantic
Thursday. Placement of the best precipitation will be somewhat
dependent on the track of the system, however there is a
frontal boundary to the NW which may help focus precipitation as
well. As such, will maintain likely PoPs across the west and
northwest and high chance PoPs elsewhere. Otherwise, after Elsa
exits to the NE, expect typical afternoon and evening showers
and storms each day through Sunday.
Typical summertime heat and humidity expected as well. After highs
in the 80s on Thursday, expect temps to rebound into the lower 90s
through the upcoming weekend.
&&
.AVIATION /01Z MONDAY THROUGH FRIDAY/...
As of 705 PM EDT Sunday...
VFR conditions at area terminals expected to persist through the
00z/5 TAF period. Some mid to high clouds will drop across RIC-
SBY late tonight in association with a passing upper shortwave,
otherwise expecting mainly clear sky /SKC/ through the night.
Some suggestions that SBY may see some patchy fog after 08z/3a
late tonight as the low level moisture increases, but not enough
confidence to include in the terminal forecast at this time.
OUTLOOK...
Primarily VFR conditions expected Monday afternoon through midweek.
&&
.MARINE...
As of 355 PM EDT Sunday...
Late this aftn, weak high pressure was over the area. Prevailing
winds were generally from the SW, S or SE at 5-15 kt. Seas were
2-3 ft and waves were 1-2 ft or less. Sub-SCA conditions are
expected for the next several days, as high pressure over the
area this evening, gradually becomes centered offshore Mon
through Wed. Generally southerly winds 5-10 kt expected tonight
into early Mon aftn. Some increase in winds is expected late
Mon into Wed night, as a bit stronger southerly flow develops
with the sfc high offshore. While a few gusts to 20 kt will be
possible into the Bay (especially in the evening/overnight), the
predominant conditions should remain below SCA criteria. Seas
will average 2-4 ft and waves in the Bay will be 1-3 ft.
Not a lot of change to the predicted track of Tropical cyclone
Elsa later in the week, with the greatest chance for the system
(or what is left of it) brushing SE portions of the local area
sometime Thu or Thu night. Follow the latest forecasts from the
National Hurricane Center for details.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...None.
&&
$$
SYNOPSIS...MRD
NEAR TERM...MAM/MRD
SHORT TERM...MRD
LONG TERM...MRD
AVIATION...MAM/MRD
MARINE...LKB/TMG
Area Forecast Discussion
National Weather Service Caribou ME
1114 PM EDT Sun Jul 4 2021
.SYNOPSIS...
High pressure will build in overnight and crest south of the
region Monday. A warm front will approach Monday night and lift
north through the area Tuesday. A cold front will cross the
area early Wednesday then stall offshore on Thursday while low
pressure approaches. Low pressure passes south of the area
Friday.
&&
.NEAR TERM /THROUGH MONDAY/...
11:15 PM Update...Rain has moved out and the sky has partially
cleared. Forecast remains on track. Only some minor adjustments
were made to temperatures.
Previous discussion:
Low pres will slowly pull away from the region this evening
w/rain tapering to showers before ending later in the evening.
The radar showed steadiest rainfall across SE Aroostook-N Washington
County into portions of central Penobscot w/pockets of heavy
rainfall. This area is where the best forcing and convergence
resides and will weaken as the low pulls away. The latest run of
the NAM and HRRR along w/the RAP matching up quite well
w/placement and timing. Using this setup, decided to push the
higher pops to the e into New Brunswick by 00Z(8PM). After
that, gradual clearing should take hold as a NNW wind takes over
later this evening w/high pres ridging in from the w. Along the
coast, received some reports of fog, so decided to keep that
going into early evening and that should lift as the offshore
winds get established. Cool night w/temps by daybreak Monday in
the upper 40s to lower 50s.
For Monday, a drier day and warmer as high pres crests over the
region. Plenty of sunshine and light WSW at 5-10 mph will allow
for afternoon temps to warm into the mid and upper 70s. Along
the immediate coast, temps could be cooler as a sea breeze gets
established by the afternoon. Another item to note is that a
Beach Hazard Statement has been issued for the immediate coast
due to the warmer air temps and cold water temps.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
Ridging will be in place Monday night with temps cooling into
the mid to upper 50s before high clouds increase later in the
night ahead of an approaching warm front. Low stratus and fog
will also advect northward from the coast ahead of the warm
front under a frontal inversion. The warm front will cross in
the morning. There is elevated CAPE and have added a slight
chance of a thunderstorm for the morning in the southern half of
the forecast area to include Bangor. The warm front will cross
during the morning into the early afternoon. In spite of the
warm advection, temps will only reach the upper 70s to lower 80s
due to the cloud cover and slow decay of the low level
inversion. This also limits SBCAPE. Most svr wx parameters are
not too impressive for Tuesday afternoon and evening to include
shear and lapse rates. Timing of the cold front is also a bit
late into the evening. There`s two separate weak upper level
shortwaves, one with the morning warm front and one approaching
in the evening with the cold front. Thunderstorms are
definitely a threat, but the only potential problem might be
heavy rainfall with high PWs up to 2 inches, dew points surging
to the upper 60s, a LLJ, a deep warm cloud layer and low Corfidi
vectors. The cold front arrives later in the night and kept the
threat of thunder in northern zones until midnight. It will be
a warm and humid night ahead of the front with lows in the upper
60s. For Wednesday, the cold front brings slightly cooler and
drier air except on the coast where offshore winds will push
Wednesday`s highs into the lower 80s. The front stalls not too
far off the coast and returns northward Thursday. High clouds
increase late day ahead of the next impulse.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Clouds thicken Wednesday night ahead of an impulse crossing the
area Thursday. Thermal packing tightens along the stalled front
Wednesday night into Thursday night with that first low tracking
south of the area Thursday and a much stronger low for Thursday
night into Friday. Between both systems, another inch or more of
rain is possible for most of the area. The second low looks
like the better producer with high PWs...possibly with TS Elsa
moisture...elevated CAPE and the RRQ of a strong upper jet. The
period Wednesday night into Friday will be mostly stable, cool,
cloudy and rainy and leaned towards cooler highs for Thursday
and Friday. The frontal boundary will be to the south during
this period with east or northeast winds. After Friday, there`s
big differences in model output between the dry GFS and wet
ECMWF. Went with chance PoPs and less clouds into the weekend
with warmer temperatures as a compromise.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
NEAR TERM:
Local MVFR possible at KBHB late this evening, otherwise VFR
through Monday. N-NW wind around 5 kts becoming WSW around 10
kts on Monday.
SHORT TERM:
Monday night into Tuesday morning...expect IFR cigs and fog to
move northward from the coast...possibly reaching as far north
as PQI by early Tuesday morning before retreating southward
again.
Tuesday afternoon and evening...VFR outside of thunderstorms.
Tuesday night into Wednesday night...VFR
Thursday into Friday...IFR cigs and tempo IFR vis in rain.
Embedded thunderstorms possible.
&&
.MARINE...
NEAR TERM: NNW winds 10-15 kts w/gusts to 20 kt tonight, w/the
higher winds over the outer zones. Seas 4-5 ft over the outer
waters, while the intra-coastal zone will see 2-3 ft. Areas of
fog and showers this evening lower vsby around 1-3 NM at times.
For Mon, W winds 10-15 kt becoming SW with gusts apchg 25 kt.
Seas 3-4 ft.
SHORT TERM: Do not foresee any advisories during the period. On
Tuesday, expect stability to cap southwesterly wind gusts to
just above 20kt. Seas may reach 5 ft at times, but if winds are
properly adjusted downward for stability, wave guidance should
stay at 5ft or less. With the stability, fog is the big concern
starting later Monday night ahead of the warm front and
continuing Tuesday and Tuesday night. Drier air should cause the
fog to retreat southward Wednesday morning, but is liable to
return later Thursday and linger into next weekend.
&&
.CLIMATE...
1.99" of rain was observed in Bangor as of 4 pm EDT this
afternoon. This broke the previous record rainfall for July 4th
of 1.33" set in 2014. This was the largest calendar day rainfall
since August 8, 2019, when 3.11" was observed.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...Beach Hazards Statement from 8 AM EDT Monday through Monday
evening for MEZ029-030.
MARINE...None.
&&
$$
Near Term...CB/Hewitt
Short Term...MCW
Long Term...MCW
Aviation...CB/Hewitt/MCW
Marine...CB/Hewitt/MCW
Climate...CB
Area Forecast Discussion
National Weather Service Cheyenne WY
820 PM MDT Sun Jul 4 2021
.UPDATE...
Issued at 812 PM MDT Sun Jul 4 2021
Updates to reflect current observations in the short term
forecast leading into Monday morning. Radar is showing a small
cell in Converse county but which should subside. Overall, winds
will remain light and skies will remain clear for the rest of the holiday
night. Enjoy!
&&
.SHORT TERM...(This evening through Monday)
Issued at 145 PM MDT Sun Jul 4 2021
Latest radar imagery showing storms developing west of the Laramie
Range in Albany County. Currently laying along the Laramie Range
near the Summit where webcams are showing pretty good
rainfall...with even a little hail being present on the Telephone
Canyon WYDOT webcam. Surface based CAPE up there not all that
impressive around 1000 J/KG with weak sfc-6km shear around 20kts.
Will need to watch though as they come off the Laramie Range.
HRRR guidance for this afternoon showing a slight slow down on
storms this afternoon. May not clear Laramie County now till maybe
7PM...but they still look to be out of the area for tonights fire
works festivities. Did have storms ending at 6PM...heading into
the southern Nebraska Panhandle after 6PM. Will continue to
monitor.
Still on track for a widespread rain event Monday as an upper
shortwave moves into southeast Wyoming during the afternoon. Still
not a lot of shear expected Monday...but given the past couple
days...it does not seem to take a lot of shear to get severe hail
out of these storms. Monday evening...sfc-6km shear really ramps
up across Converse/Niobrara Counties into the northern and central
Nebraska Panhandle...so could be a late show for severe storms
Monday evening. Forecast storm motions pretty low...generally
under 10-12kts...so some areas could see quite a bit of rainfall
east of the Laramie Range. PWATS near an inch for areas east of
the Laramie Range Monday afternoon...increasing to 1.25 inches
Monday evening. We may need a Flash Flood Watch for some areas.
ECMWF much slower on rain ending Tuesday...keeping QPF in the
Panhandle through Tuesday afternoon. Did hold onto some high
chance to likely PoPs for Tuesday afternoon.
.LONG TERM...(Tuesday night through Saturday)
Issued at 141 AM MDT Sun Jul 4 2021
As a high pressure sits over the southwest CONUS, the deep
subsidence will suppress any convection and keep temperatures warm
through Friday night with highs in the upper-80s and 90s expected
and lows in the upper-50s and 60s. Friday into Saturday a more
unsettled pattern moves in when a low pressure system drops through
the central plains, creating a northwest flow aloft, advecting
cooler air into the region and increasing chances for showers and
thunderstorms, especially for the Nebraska panhandle. The southwest
corner of the CWA will likely still be impacted by the high pressure
system to the southwest, so the chances of showers and thunderstorms
are very low there. Current PoPs are still low across the CWA though
due to uncertainty in spread and intensity of showers and
thunderstorms.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 538 PM MDT Sun Jul 4 2021
VFR prevails for the majority of terminals through the TAF period.
Isolated / widely scattered showers and thunderstorms will persist
through about 03z before dissipating. Locally MVFR ceilings and/or
visibilities are possible beneath heavier cores, but gusty/erratic
surface winds will be the primary aviation hazard along with local
turbulence. Otherwise, expect SCT/BKN sky conditions around 10k ft
AGL through Monday. Thunderstorms are likely to return to the area
Monday afternoon. VCTS will likely need to be introduced for later
TAF issuances.
&&
.FIRE WEATHER...
Issued at 145 PM MDT Sun Jul 4 2021
Minimal fire weather concerns over the next couple days as
monsoonal moisture remains in place for afternoon showers and
thunderstorms. Have a low pressure system moving through southeast
Wyoming Monday afternoon and evening...which will bring
widespread chances for wetting rains and thunderstorms. Humidities
above critical levels in the 20s and 30s in the afternoon...with
good to excellent overnight recoveries. Still looking at a drier
and more more breezy weather pattern from Wednesday on into the
end of the week...that could bring critical fire weather
conditions along and west of the Laramie Range.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
UPDATE...AW
SHORT TERM...GCC
LONG TERM...LK
AVIATION...CLH
FIRE WEATHER...GCC
Area Forecast Discussion
National Weather Service Dodge City KS
541 PM CDT Sun Jul 4 2021
...Updated mesoscale discussion...
.MESOSCALE DISCUSSION...
Issued at 533 PM CDT Sun Jul 4 2021
Well it turns out the HRRR was the odd man out and completely failed
to capture reality of the storms that are currently ongoing. Meso
analysis suggests that there is plenty of CAPE and marginal shear
for low end supercells to continue for the next hour or two.
Areal coverage of WSR-88D is increasing over the last hour.
Eventually do expect a threat change (from increased beneficial
competition... ) the hail risk will decrease and the wind threat
will increase. We probably still have another good hour or two
before this threat changes based of radar and short term guidance
trends. Additionally, upscale growth will probably develop later
on in the storm evolution.
&&
.SHORT TERM...(This evening through Monday)
Issued at 222 PM CDT Sun Jul 4 2021
Well humans will not being the only thing that is sparking off some
excitement tonight. The atmosphere will be too. Spoiler alert: think
the atmosphere will win tonight in terms of impacting weather across
southwest Kansas. Early afternoon surface analysis shows that a low
as formed across far southeast Colorado. A field of stratocu to cu
has developed across far southwest Kansas and northward towards Hill
City. This is the area to watch for storm development. Meso models
like the ARW, NSSL-WRF, RRFS and global models like the EC all break
out convection in this general area late this afternoon. The HRRR seems
to be the odd man out and keeps the area devoid of convection. Looking
at this model more closely, there is no CAP present, so not so sure
why this model is being conservative with convective growth. Looking
at satellite water vapor channel shows a subtle wave moving through
the greater region, so this is upper level support to help trigger
storms. This upper level wave will also increase bulk shear to 30 knots
this evening, so there will be marginal shear that is supportive of
marginal supercell structures.
Right now, have the highest pops aligned with the latest thinking that
storms will develop along the Highway 83 corridor this afternoon. Storm
movement should be to the south. Forecast Skew-t`s/log-p`s show a profile
that is favorable for large (1-2") hail and damaging winds. PWATs are
high right now, so there should be some beneficial competition on hail
embryos to cut down on any significantly larger hail (2+"). Anticipated
upscale growth should then transition the hail threat to a wind threat.
The low level hodograph and thermo profile is not favorable for tornadoes.
Hail with the initial supercell like structures, followed by outflow
winds of 60+ mph, and heavy rainfall are the main threats for this
event. Those citizens, particularly west of Dodge City, should heed
any warning, take shelter indoors, and post-pone the fireworks until
it is safe to resume to do so. A large downburst with fireworks can
be extremely dangerous and lead to an uncontrolled fire. Bottom line,
pay attention to the weather for tonight if you are outside.
All this activity should exit the FA by 10 or 11 pm plus/minus an
hour.
The atmosphere should be pretty worked over on Monday. The net result
is a dry forecast with a high around 90F. Winds will be relatively
light throughout the day.
Overnight mins heading into Tuesday morning will be seasonal with values
mainly in the mid to upper 60s.
.LONG TERM...(Monday night through Sunday)
Issued at 222 PM CDT Sun Jul 4 2021
The EC is still indicating a fropa late Tuesday and into Wednesday.
Convection will still be possible along this front also also behind
in the post-frontal upslope flow pattern. The NBM pops look fine enough
for now during this period.
After a brief cool down midweek, highs will quickly rebound to seasonally
hot values with 90s likely by the end of the business week.
Friday could end up being the warmest day as we enter the tail end of
the westerlies with some downslope component to the winds. Upper 90s
may be realized here. Don`t see any guidance to suggest warmer than
than that currently.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 515 PM CDT Sun Jul 4 2021
Scattered thunderstorms will continue to develop and spread south-
southwest across portions of southwest and central Kansas through
late evening, potentially affecting the vicinity of all TAF sites.
Otherwise, primarily VFR conditions are expected to prevail through
early Monday morning. South-southeast winds around 10 to 20kt are
forecast to persist through early Monday as a weak lee side trough
of low pressure remains anchored in eastern Colorado.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 68 90 67 90 / 60 10 0 10
GCK 66 89 65 88 / 60 10 0 20
EHA 64 90 65 87 / 60 10 10 40
LBL 66 89 66 87 / 60 10 0 20
HYS 67 90 66 91 / 20 0 0 20
P28 70 90 67 92 / 20 10 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE...Sugden
SHORT TERM...Sugden
LONG TERM...Sugden
AVIATION...JJohnson
Area Forecast Discussion
National Weather Service Duluth MN
713 PM CDT Sun Jul 4 2021
.DISCUSSION...(This evening through Saturday)
Issued at 444 PM CDT Sun Jul 4 2021
Summary: Shower and thunderstorm chances this evening and tonight
ahead of a cold front. Another hot day Monday before a system
bring rains and cooler temperatures on Tuesday. Cooler
temperatures and periodic rainfall chances persist for the
remainder of the week before warming into the weekend.
A cold front was draped from near International Falls to
southeastern South Dakota this afternoon with an area of low
pressure just to the north of the International Border west of
Thunder Bay. This front will slowly drop southeast this evening
and lead to the development of showers and thunderstorms. The
airmass ahead of the front is characterized by CAPE of 2000-3000
J/kg with effective shear around 20-30 knots. However, 700mb
temps are currently in excess of 10C, which is stifling
development for the most part. As we get closer to 00Z-01Z, RAP
soundings indicate cooling at 700mb and convective initiation
occurring. CAMs have backed off on the coverage of thunderstorms
through the day, with the HRRR developing a few storms north of
the Iron Range into the Arrowhead before quickly falling apart.
Additionally, water vapor imagery shows dry air pushing across
northwestern Minnesota into north-central Minnesota, which may be
what the CAMs are keying in on with the reduction in coverage of
showers and storms this evening. With that said, if a storm can
develop in the airmass ahead of the front, a few severe storms
will be possible with DCAPE around 1300-1440 J/kg leading to
mainly a damaging wind threat. Some hail around 1 inch in diameter
will also be possible with localized heavy downpours as PWATs
remain in the 1-1.5 inch range.
Any shower/thunderstorm activity looks to be mainly clear of the
region by 06Z with quiet conditions expected for the early
morning hours. Despite the breezy northwest winds on Monday,
temperatures will remain hot for one more day. Highs will be in
the 80s and lower 90s with dewpoints in the 50s and 60s leading to
muggy conditions. Drier air will move into northern Minnesota
through the day, helping to bring Tds down and making things a bit
more comfortable. Looking ahead to Tuesday, a shortwave will move
through the region with surface low pressure developing across
southern Minnesota. This will bring widespread rainfall to the
region Tuesday into Tuesday night and areas from the Brainerd
Lakes area into parts of northwest Wisconsin may see in excess of
an inch of badly needed rainfall if everything comes together
right. Temperatures will also trend cooler with highs in the 60s
and 70s. Not overly excited about any severe potential at this
time given the differences in timing and coverage with the models,
but it definitely looks like a rain maker for much of the region.
High pressure will then dry things out for Wednesday before
another chance for showers and storms Thursday night into Friday
as another trough swings through. Temperatures will remain near to
slightly below normal through the remainder of the week before
returning to near to slightly above normal levels by the weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 713 PM CDT Sun Jul 4 2021
Scattered showers and thunderstorms have formed south of INL to
north of BRD. At this moment, not expecting them to affect the
terminals directly, and have a VCSH until a better resolution to
timing can be gleaned from radar and satellite trends. The
potential for this activity to affect the other terminals is also
in question, but will continue to monitor and update as needed.
Otherwise, VFR through the forecast. Gusty winds early in the
forecast will diminish toward sunset. Look for gusty winds by mid
morning Monday.
&&
.MARINE...
Issued at 444 PM CDT Sun Jul 4 2021
A chance of a few strong to severe storms will persist this
evening across the nearshore waters before clearing for the early
morning hours. Heavy downpours, lightning and gusty winds to
around 40 knots are the primary threats with some hail being
possible as well. Winds will turn southwesterly overnight and then
slowly become northwesterly by the end of the day Monday.
Northeasterly winds will then develop on Tuesday and persist into
Wednesday. Winds are currently expected to remain around 20 knots
or less during this time, but the prolonged period of
northeasterly winds may lead to building waves at the head of the
lake and in the outer Apostle Islands. Wave heights of 2 feet or
less will be seen through Monday, outside of any thunderstorm
activity this evening, before building to 1 to 3 feet along the
South Shore and west of Silver Bay Tuesday.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 68 89 57 67 / 20 0 10 80
INL 63 84 52 66 / 10 0 30 50
BRD 67 92 61 71 / 10 0 30 80
HYR 67 90 61 75 / 20 0 10 80
ASX 68 90 57 70 / 30 0 10 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&
$$
DISCUSSION...BJH
AVIATION...GSF
MARINE...BJH
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
940 PM CDT Sun Jul 4 2021
.UPDATE...
With loss of heating after sunset, area radars show showers and
thunderstorms have dissipated, except for a patch of rain from
debris clouds approaching San Antonio. This rain will dissipate in
the next hour, as well. Have removed POPs for the rest of this
evening into the overnight hours, however cannot rule out very
isolated showers. With a moist tropical airmass, expect redevelopment
of showers and a thunderstorm or two toward morning. Earlier
thunderstorm outflows have cooled the airmass faster this evening.
Have reestablished temperature and wind trends for the remainder of
tonight. Otherwise, ongoing forecast is on track with more rounds of
showers and thunderstorms during the week ahead. Locally heavy rains
and minor flooding can be expected, along with gusty winds due to
thunderstorm outflows.
&&
.PREV DISCUSSION... /ISSUED 634 PM CDT Sun Jul 4 2021/
AVIATION...
SHRA/TSRA are nearly stationary near KEDC and will go with VCSH at
KAUS for this evening. SHRA/TSRA are slowly moving toward KDRT and
will go with VCSH there for this evening, as well. Expect SHRA/TSRA
to gradually wane with loss of heating with no other impacts to the
sites later this evening into the overnight. A moist airmass remains
and expect SHRA/TSRA to redevelop toward morning, then increase on
Monday with heating. Have maintained the SHRA/VCTS for the day and
PROB30s with restrictions for VSBYs for late morning into afternoon.
Otherwise, VFR conditions this evening will lower to MVFR overnight
and IFR toward morning. CIGs gradually rise to MVFR late morning and
VFR in the afternoon. Winds will be less than 10 KTs, however gusts
to 30 KTs are possible in and near SHRA/TSRA.
PREV DISCUSSION... /ISSUED 207 PM CDT Sun Jul 4 2021/
SHORT TERM (Tonight through Monday Night)...
Control+C, Control+V. You could pretty much copy and paste
yesterday`s forecast with today`s forecast. The only small
difference is the lack of a meaningful mid-level impulse rounding
the eastern periphery of a Subtropical Ridge to the west of the CWA.
So far today, coverage has actually been quite a bit higher than it
was on Saturday, as high cirrus and residual cloud cover managed to
thin out a bit sooner. Additionally, an outflow boundary stabilized
locations to the north of the Highway 21 corridor yesterday, and
that has not been the case today, allowing for widespread isolated
showers and storms. Rainfall rates have been rather impressive, with
several sites in the LCRA network picking up a quick 1-2" in less
than 30 minutes. These types of rainfall rates will be common again
through early evening as any storm that forms will have plenty of
moisture to tap into. With PWATs up around 2.1-2.4", and sfc Td`s in
the 71-79 range, locally heavy downpours are and will continue to be
the primary concern. Minor flooding could occur if any storms sit
over a location for more than 30 minutes, especially given these
crazy high rainfall rates.
The forecast remains largely unchanged for this evening. With
numerous events taking place through early evening and into late
evening, it`s a good practice to continue monitoring the forecast as
isolated to scattered showers and storms will continue through at
least 8pm. Storms should be largely diurnally driven, so coverage
should rapidly decrease around or shortly after sunset. This should
result in a quiet later evening period for the region on this 4th of
July Holiday.
Monday will feature yet another chance for showers and storms.
Latest 12Z CAMs, like the FV3, ARW, TTU-WRF, and even the 12Z HRRR
are extremely bullish on the development of widespread showers and
thunderstorms in the afternoon and evening...I`m not buying it yet
given the poor performance of hi-res guidance the last few days, but
can you really blame `em? In general, expect another diurnally driven
event, with showers and thunderstorms developing by around
lunchtime, with the threat continuing into the evening hours. Storms
should weaken and move out of the area after 9pm. For what it`s
worth, WPC still has most of the area within a Marginal risk in their
Excessive Rainfall Outlook for Monday.
LONG TERM (Tuesday through Sunday)...
Not much change to the going forecast overall as we look to remain
in a cool, wet pattern through at least Thursday that may continue
into and perhaps even through next weekend. By Tuesday morning a
broad closed upper low will be in place along the gulf coast.
Although lowered H5 heights and resultant vort maxes will be
somewhat transient in amplitude and location, model guidance remains
in agreement that much of south-central Texas will see several
rounds of scattered to at times numerous showers and thunderstorms.
Consensus is that overall QPF through the week will likely be
highest over the southern half of the CWA, where widespread 2-4"
totals with locally higher amounts are expected. Along our northern
border, more on the order of 0.5-1.5" for the most part. The
greatest coverage and intensity will come each afternoon into the
early evening, but isolated activity is still expected most
overnights and mornings. Given the slow-moving nature of the
activity each day and high atmospheric moisture content, the risk
for excessive rainfall to impact isolated locations will exist
through at least Thursday. After that, there`s added uncertainty in
the location and strength of the upper disturbance with some hints
that it will shift west and bring the focus for heavier rain to our
west/southwest counties. There is also the possibility that a
surface low attempts to develop late this week, increasing onshore
flow and convergence and leading to a continued risk for locally
heavy rain. Some may notice the absolutely insane CMC solution,
which leaves a closed low overhead and produces unbelievable amounts
of QPF across parts of the area Friday into Saturday. This can
certainly be discounted as an unrealistic outlier, but it is not out
of the question that isolated spots see 4-6+" rain totals by the end
of the long-term period and the potential is there for these amounts
to occur in a relatively short amount of time on any day this week.
Expect seasonal lows mainly in the 67-77 degree range, with cool
highs in the 80s to near 90. If indeed the drier solution were to
win out into next weekend, we`d see a warming trend begin, but in
the meantime high temps will run 5-10 degrees below normal for early
July this week.
PREV DISCUSSION... /ISSUED 1213 PM CDT Sun Jul 4 2021/
AVIATION (18Z TAFS)... /NEW/
Widely scattered showers and occasional thunderstorms are expected at
all three I-35 sites this afternoon and early evening. All sites will
be at risk for very heavy downpours in any storms that manage to go
over the 5 mile radius. Expect gusty winds briefly with any storms,
thus, have inserted at TEMPO at AUS through 21Z and through 22Z at
SAT/SSF. Believe that DRT should stay dry for the most part, but
cannot rule out a stray shower this afternoon through about 01Z.
Expecting VFR CIGs to make a return by early evening across the
board. Any showers or storms should come to an end by 01Z, followed
by MVFR CIGs by 09Z at AUS/SAT/SSF. IFR CIGs look like a good bet by
12Z at all three sites. More storms are expected on Monday,
especially after 18Z but confidence is low, so have gone with a
PROB30 for AUS/SAT for now.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 74 88 74 88 73 / 30 70 50 60 30
Austin Bergstrom Intl Airport 74 88 72 88 71 / 30 70 50 60 30
New Braunfels Muni Airport 74 89 74 87 73 / 30 70 50 60 40
Burnet Muni Airport 73 86 71 86 71 / 30 60 40 60 30
Del Rio Intl Airport 78 94 76 90 74 / 20 60 50 60 40
Georgetown Muni Airport 73 86 72 87 72 / 30 60 40 60 30
Hondo Muni Airport 75 88 73 85 72 / 30 70 50 60 50
San Marcos Muni Airport 74 88 72 87 72 / 30 70 50 60 40
La Grange - Fayette Regional 74 89 74 88 74 / 30 60 50 70 30
San Antonio Intl Airport 75 87 74 86 73 / 30 70 50 60 40
Stinson Muni Airport 77 89 75 87 75 / 30 70 50 60 50
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Short-Term/Aviation...04
Long-Term...YB
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
654 PM CDT Sun Jul 4 2021
.DISCUSSION...(This evening through Sunday)
Issued at 248 PM CDT Sun Jul 4 2021
Chances for thunderstorms this evening have continued to trend
downward. A few of the 12Z CAMs redevelop convection of our north
and west, but the HRRR has been insistent that we will stay
completely dry. Latest satellite shows some agitated CU in our
southwest. As such, the latest forecast package retains some
slight PoPs, but the expectation is that most, if not all, of the
forecast area will be dry. In the case that storms do develop,
there is a chance that some could be on the strong side, but the
higher threat for this will be to our southwest where higher
instability is coincident with around 30kts of effective shear.
Monday and Monday night should also remain dry across the area,
with most models keeping convection well to our west. High temps
are expected to range from 92 to 97 degrees. Light winds and 60-70
degree dewpoints will make it feel even hotter. Even so, it
appears we will remain below of heat advisory criteria (heat
index 105 degrees or more).
Better chances for showers and thunderstorms arrive as a cold front
moves through the area on Tuesday. With ample instability and
stronger forcing, a few strong to marginally severe storms are
possible, but lackluster shear should help mitigate any organized
severe threat.
A few showers or dissipating thunderstorms may linger through
Tuesday night into Wednesday morning, but most of the daytime should
be dry with high temperatures dropping back into the 80s.
Temperatures will then quickly rebound Thursday and Friday ahead
of a another upper trough and surface cold front. Highs may reach
the upper 90s for portions of the area by Friday. This cold front
will then move through the area, bringing another chance for
thunderstorms to the area Friday evening and overnight. Behind
this cold front, we will see much cooler and drier air for next
weekend.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Tuesday)
Issued at 637 PM CDT Sun Jul 4 2021
VFR conditions are forecast. Very small chance of some nearby
convection for a short time this evening near a lingering boundary,
but even the short term VCTS in the forecast will probably not
even be needed.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
DISCUSSION...Mangels
AVIATION...Heinlein
Area Forecast Discussion
National Weather Service Grand Rapids MI
732 PM EDT Sun Jul 4 2021
LATEST UPDATE...
Aviation
.SYNOPSIS...
Issued at 305 PM EDT Sun Jul 4 2021
- Beach Hazard and marginal severe risk Monday
- Marginal excessive rainfall risk with general thunder Wed
- Heavy rain and thunderstorm possible Fri night through Sun
&&
.DISCUSSION...(This evening through next Sunday)
Issued at 305 PM EDT Sun Jul 4 2021
- Beach Hazard and marginal severe risk Monday
Wow...what great weather for a Pure Michigan 4th of July weekend!
Latest HRRR along with other HREF ensemble guidance indicates
winds will increase enough along the coast north of Grand Haven to
reach marginal SCA and beach hazard conditions as early as 09Z
Monday. Given the holiday weekend and number of people enjoying
the weekend...opted to go with the headlines to raise awareness.
SPC increased the area of the marginal risk for Monday as well and now
covers most areas north of a Holland to Alma line. Although there
is not much in the way of storms upstream at the present
time...we do have a pretty nice elevated mixed layer in place with
H85 temps at 20C and 850 - 500 mb lapse rates of >7C/KM. Couple
that with sfc dewpoints and that all translates into ML CAPE >
1,500 J/Kg and DCAPE > 1,000 J/Kg. The shear is however weak with
roughly 20kts of 0-3km shear. So the bottom line threat would be
for a few storms with damaging wind and possibly to a lesser
extent large hail.
The trigger for potential severe weather will be the front and
associated digging upper level trough that is now over the
Dakotas. While most of the energy stays north of the area...there
will still be sufficient lift to get scattered storms going along
the front as it stalls over us by Monday evening. There will also
be a decent amount of moist transport into the boundary such that
localized excessive rain and resultant flooding will also be a
threat by early Tuesday morning.
- Marginal excessive rainfall risk with general thunder Wed
Same front but on a different day or something like that goes the
saying. Anyhow...the front is expected to pull back to the north
as a warm front on Tuesday as another wave of low pressure
approaches Michigan from the west. The next wave is stronger but
most of the upper level energy will again pass a bit north of our
area on Wed and with it most of the rain and storm potential.
However...there will be chance of a thunderstorm or two most on
Wednesday (ML CAPE ~ 1000J/KG) as the front finally returns as a
cold front and pushes well south of Michigan. Behind the front
drier air and seasonable temperatures will settle in for Thu.
- Heavy rain and thunderstorm possible Fri night through Sun
Potentially another busy weekend for meteorologists...ECMWF
ensemble seems to be locking into developing a fairly significant
upper level trough across the plains with MI squarely in the
right front exit of the associated jet stream. That will set us up
for several rounds of heavy rain chances along with severe storm
potential starting Friday night and continuing through the
weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 727 PM EDT Sun Jul 4 2021
The atmosphere will remain relatively dry through the period
limiting the sky cover...especially in the lower levels. Gusty
southwest winds are expected to develop Monday...especially away
from the lakeshore. A small risk for an afternoon thunderstorm
exists Monday afternoon...mainly to the north of KMKG and KGRR.
&&
.MARINE...
Issued at 305 PM EDT Sun Jul 4 2021
Small Craft Advisory north of Grand Haven for Monday. After a near
perfect day for nearshore recreation a frontal system will begin
to approach from the north early Monday. South-southwest winds
will increase ahead of the front with some choppy waves building
3-4 feet. The roughest water should be off the Little and Big
Sable points.
Scattered thunderstorms are also possible late Monday afternoon
and evening as the cold front pushes slowly southward. Areas of fog
and low clouds are also increasingly likely by Tuesday morning
north of South Haven. The threat of storms will continue through
Tuesday night.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement from 5 AM EDT Monday through Monday
evening for MIZ037-043-050.
LM...Small Craft Advisory from 5 AM to 11 PM EDT Monday for
LMZ847>849.
&&
$$
SYNOPSIS...Cobb
DISCUSSION...Cobb
AVIATION...MJS
MARINE...Cobb
Area Forecast Discussion
National Weather Service Lubbock TX
639 PM CDT Sun Jul 4 2021
.AVIATION...
Showers and thunderstorms are possible later this evening into the
early morning hours Monday. Chances will increase for storms in
the vicinity of KPVW and KLBB around midnight tonight, with lesser
chances at KCDS. Light rain showers will persist on and off
after sunrise behind the early morning thunderstorms. More
thunderstorm are possible Monday afternoon but timing and location
is too uncertain at this time for mention in the TAFs.
&&
.PREV DISCUSSION... /issued 155 PM CDT Sun Jul 4 2021/
SHORT TERM...
Northwest flow storms will be the main story over the next 24 hours
with a potential for severe weather associated with this activity.
An upper level ridge will be centered over the four-corners region
today through tomorrow. We may see some upper level support with
convection this evening and overnight. A short wave was diving
southward on the east side of the upper ridge. A weak speed max at
250mb was also over Colorado following this short wave trough. The
latest RAP analyzes this speed max around 45kt and will shift
farther to the southeast into the Texas Panhandle this evening. This
feature was already initiating thunderstorms in the eastern Texas
Panhandle this afternoon. A surface pressure trough has formed in
eastern New Mexico in response to this upper level shortwave over
the Central Plains. A north-south oriented frontal boundary extends
farther north from northeastern New Mexico. Initial development of
widespread convection will be favored along this boundary and will
not likely reach the extreme southwestern Texas Panhandle until
after 00Z. Storms that do maintain their strength as they move out
of the Panhandle will be met by very rich low level theta-e air.
However, given how moist the atmospheric column has been over the
past few weeks, lapse rates will not be too impressive over the
South Plains. Much stronger mid level lapse rates will exist farther
north which will allow progged CAPE values to taper off the farther
south you travel. Despite the weak lapse rates, very moist low
levels of the atmosphere will allow for 0-1.5km mixed layer CAPEs
peaking around 1500-2000 J/kg. The 0-1.5km layer looks to be the
most representative average mixed layer today across the entire
South Plains region. Increasing CIN over the South Plains during the
late evening hours and overnight will likely limit the southern
extent of convection. Deep layer shear will further increase this
afternoon and evening ahead of an expected convective complex. This
should be able to garner some organization to the convection into
the South Plains. Although storms will be fairly quick moving, heavy
rainfall and flooding will still be possible. Precipitable water
values are still abnormally high for this time of year which will be
able to generate heavy rainfall.
LONG TERM...
Isolated-to-widely scattered rain showers and thunderstorms are
forecast to develop Tuesday afternoon and evening, especially across
the western portions of the CWA where low-level convergence is
greatest in vicinity of the surface trough. A multi-cellular storm
characteristic is expected once again, and it is uncertain just how
far south the cold front will move late Tuesday into Wednesday,
which may have implications on mean convective movement (i.e.
advection vs. propagation). Regardless, a localized risk for flash
flooding given saturated soils as per recent West Texas Mesonet data
will be possible as little drying of the ground is forecast through
mid-week. If the cold front is able to cross into the Texas Panhandle
region, an isolated wind-damage risk may also develop within the
best-organized cold pools as multi-cells would attempt to transition
into loosely-organized line segments. The front is then forecast
to move northeastward on Wednesday as a weakly baroclinic trough
pivots across the northern Great Plains and into the Upper Midwest,
with the mid/upper-level ridge centered over the Desert Southwest
expanding eastward Wednesday into Thursday. Precipitation chances
will decrease accordingly with warm-to-hot temperatures forecast
given the gradual build in geopotential heights by the end of next
week.
Sincavage
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
55
Area Forecast Discussion
National Weather Service Phoenix AZ
410 PM MST Sun Jul 4 2021
.SYNOPSIS...
Good chances for showers and thunderstorms will continue today
across eastern Arizona with isolated storms possible into the south-
central Arizona deserts. Heavy rainfall capable of producing flash
flooding will be the main impact. Much drier conditions will then
settle in for Monday through at least Wednesday with only isolated
storm chances over the eastern Arizona high terrain. Temperatures
will also warm to a few degrees above normal for much of the coming
week with highs mostly in a 109 to 112 degree range across the lower
deserts. A gradual return of monsoon moisture should bring back more
widespread rain chances by next weekend.
&&
.DISCUSSION...
Central Arizona is currently situated between two smaller mid-
tropospheric anticyclonic circulations, one across the central Baja
peninsula and another south of the Four Corners. Latest satellite
imagery also reveals the lingering vort max across northern Sonora,
which has helped to already initiate convection across southern
Arizona. Meanwhile, latest observations reflect what is typically
seen the day after widespread shower and thunderstorm activity.
Temperatures across south-central Arizona are struggling to reach
the 100 degree mark, while dewpoints are well above normal in the
mid to upper 60s. PWATs are also running near all-time daily records
with the PSR morning sounding registering 2.01 inches. Theres been
little change during the day indicated by the latest KPHX ACARS
sounding at 2.08 inches.
The abundant moisture is yielding a widespread area of MLCAPE above
1000 J/kg across southern and eastern Arizona, while mid-level lapse
rates are weak and near moist adiabatic. Latest mesoanalysis
indicates a dearth of DCAPE and consequently the chance of strong
winds and blowing dust is low. Convective parameters essentially
point to the potential for heavy rain this afternoon and evening.
Weak steering flow will also result in slow-moving storms capable of
producing flash flooding, particularly across the burn scars in the
higher terrain east of Phoenix.
Convection has already initiated across far southwestern Maricopa
County and additional isolated storms are likely to develop across
the higher terrain north and east of Phoenix this afternoon.
However, CAMs including the time-lagged HRRR continue to trend
towards less overall coverage. This is largely due to a pronounced
warm and dry layer evident around 800 mb, which is resulting in
detrimental convective inhibition, generally from Phoenix westward.
Nevertheless, an isolated cell or two in the Valley remains a
possibility, given the excessive moisture. PoP for this evening has
been lowered based on the latest trends in the NBM and several CAMs.
A few models also hint at the possibility of early morning shower
activity across the lower deserts and this certainly cant be ruled
out, considering there will likely be areas of leftover instability.
&&
.PREVIOUS DISCUSSION...
The westerly drying will continue Monday into Tuesday with a
capping inversion aloft likely shutting down storm chances in all
but the high terrain on Monday. By Tuesday, afternoon surface dew
points are seen dropping into the 40s areawide and PWATs lower to
around 1.00" resulting in only a few isolated storms possible over
far eastern Arizona. The upper level ridge center is forecast to
shift into Nevada Tuesday before drifting back over southern Utah
and northern Arizona later in the week. H5 heights will also
increase slightly reaching 591-594dm across the Desert Southwest.
The drying boundary layer and increased heights aloft should push
daytime highs to around 110 degrees in the Phoenix area to 110-113
degrees across the western deserts for Tuesday and Wednesday.
After the somewhat dry period during the half of the week, models
remain in good agreement showing modest moisture return out of the
east and northeast once the high center shifts closer to the Four
Corners area. The moisture advection may start as early as
Wednesday, expanding through much of southern Arizona on Thursday
and Friday. This should expand storm chances westward by next
weekend, but as usual chances will be greater over the eastern
Arizona high terrain. Temperatures may also begin to moderate
slightly late in the week as moisture increases, but we will be
going against a strengthening ridge as ensemble output agrees the
ridge center strengthens and H5 heights increase to around 598dm
just to our north.
&&
.AVIATION...Updated at 2310Z.
South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:
West winds 10-15kt will continue through mid evening, then looking
at the possibility of a distant outflow boundary turning the
direction to east. HREF guidance shows a 30-40% probability of
outflow winds exceeding 30 kts this evening during a 02Z-05Z time
frame. NBM output shows around 15% chance of storms this evening and
overnight, but have no mention in these TAFs. SCT-BKN clouds mostly
aoa 10 kft will continue throughout much of the period. NBM storm
chances at any site Monday is less than 10%.
Southeast California/Southwest Arizona including KIPL and KBLH:
Winds will continue to favor a southeast to southwest component at
the terminals through the next 24 hours with speeds mostly remaining
aob 12kts. FEW clouds are expected through the period with bases
remaining aoa 10 kft.
&&
.FIRE WEATHER...
Wednesday through Sunday:
Moisture will decrease gradually through the midweek period, which
will generally confine the threat of storms to the eastern Arizona
high terrain. A return of deeper moisture looks likely late in the
week with storm chances potentially increasing and expanding
westward across Arizona. Temperatures for the bulk of the period
will run a few to several degrees above normal. Min RH values will
generally be in a 10-20% range midweek with higher values over the
higher terrain before improving to 15-25% late in the period. Max
RHs will recover into the 30-45% range for most locations. Apart
from thunderstorms, wind patterns will follow diurnal patterns.
&&
.SPOTTER INFORMATION STATEMENT...
Spotters should follow standard reporting procedures.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
DISCUSSION...Hirsch
PREVIOUS DISCUSSION...Kuhlman
AVIATION...Smith/18
FIRE WEATHER...Hirsch/Kuhlman
Area Forecast Discussion
National Weather Service Tallahassee FL
421 PM EDT Sun Jul 4 2021
.NEAR TERM [Through Monday]...
For the next 24 hours, heavy rainfall and flooding will the the main
concern, mainly over our Florida counties along and south of I-10,
with coastal counties being at most risk. A flood watch has been
issued for portions of the Florida panhandle and western big bend
and is in effect through Monday.
There is quite a north-south moisture gradient over the forecast
area. Satellite-derived PW values range from barely 1" north of
Albany to a rich, juicy, tropical 2+" south of I-10. Meanwhile,
there is moderate westerly flow through the mid-upper levels,
running parallel to the gradient. Upwind, water vapor imagery
shows a slow-moving vort max now rounding into the base of the
eastern U.S. trough.
The vort max is expected to slowly slide east, slinging the
deeper moisture just a little further inland through tonight. An
associated surface pressure fall along the boundary will bring a
more southerly turn of surface winds from the Gulf into our
coastal counties. This should help a slow-moving east-west stripe
of heavy rainfall to develop later tonight, particularly along
and south of FL Highway 20. These areas have already seen heavy
rain in recent days, so it will not take as much rain as usual to
get flooding. Some but not all of our CAMS guidance is showing
small pockets of rainfall totaling 3-7 inches through Monday
afternoon, with the 12 HRRR showing a locally heavier pocket over
inland Bay/Calhoun Counties.
Coastal Taylor and Dixie Counties got quite a few inches of rain
this morning prior to sunrise, so that area is also vulnerable.
Lows tonight will be in the lower 70s and highs Monday in the mid
to upper 80s.
.SHORT TERM [Monday Night Through Tuesday Night]...
The official NHC forecast track for TS Elsa as of early Sunday
afternoon shows the center emerging into the far SE GOMEX Monday
night after crossing Cuba. Elsa then tracks to the NNW through
Tuesday night with the center remaining just offshore of the
southwest coast of Florida through Tuesday evening before turning to
the NNE and making landfall north of Tampa just south of Dixie
County as a tropical storm. Since this forecast track and intensity
may change, all interests along the northeast Gulf including inland
counties of the Florida Big Bend should listen to latest advisories
on Elsa for possible tropical storm watches and or warnings. Should
this forecast go as planned, our CWA is still expected to see a
continuation of above seasonal chances for showers and
thunderstorms, some with torrential downpours, as a surge of
tropical moisture lifts over our region with the increasing
southeasterly flow ahead of the system. Rainfall amounts of 2 to 4
inches with isolated higher totals will be possible with Elsa, with
the greatest chance for heavy rain across the SE Big Bend. Also our
local area will still likely experience breezy winds, rough marine
and beach conditions, and potentially some storm surge in Apalachee
Bay. Impacts are most likely to begin by Tuesday evening/Tuesday
night, but could begin as early as daytime Tuesday if Elsa`s
forecast track speeds up. Forecast surge in Apalachee Bay will be
highly sensitive to any track and intensity changes with Elsa, so
specific values are still a bit difficult to pin down at this time.
High temperatures are forecast in the middle 80s with low
temperatures in the low 70s.
.LONG TERM [Wednesday Through Sunday]...
The official NHC forecast tracks Elsa NEWD across northeast FL
Wednesday and then the coastal areas of GA and the Carolina`s
Thursday. Rain chances will remain likely (60-70%) on Wednesday
with a gradual return to a more summerlike pattern by the end of
the work week into the weekend. Highs will be in the upper 80s to
around 90 with lows in the lower 70s.
&&
.AVIATION...
[Through 18Z Monday]
The next 24 hours will feature two sloppy periods at the
terminals. The first will come this afternoon due to the more
routine process of thermal lift leading to afternoon showers and
thunderstorms. The air mass is driest at ABY, so confidence is
lowest there.
Along the coast at ECP, there may be very little break this
evening before a trough of low pressure slowly lifts north out of
the Gulf. This will bring a late evening through morning round of
rain and thunderstorms to the FL terminals, lifting north to the
AL/GA terminals later on Monday morning. Otherwise, some near-
sunrise low stratus is possible at inland terminals given the
moist low-level environment.
&&
.MARINE...
A stalled cold front across the Florida panhandle will dissipate
on Monday. South of the front and until the front dissipates,
moderate to occasionally fresh west breezes will prevail over the
waters. Tropical Storm Elsa is forecast to move northwest through
the Straits of Florida and enter the southeast Gulf on Monday
night. Mariners should monitor the progress of Elsa. At this time,
tropical storm conditions could occur over the northeast Gulf as
early as Tuesday, but more likely Tuesday night. The waters east
of Apalachicola stand a higher chance of tropical storm force
winds than the waters west of Apalachicola.
&&
.FIRE WEATHER...
There are no fire weather concerns at this time with very wet
conditions in place.
&&
.HYDROLOGY...
Widespread rainfall totals over the next couple of days will be
around 2 inches south of the Florida border. However, some areas
in the FL panhandle west of Tallahassee are forecast to get 3-5
inches of rain, BEFORE we get any of the rain from Elsa. Some of
the CAMs are showing that isolated amounts of 6-8 inches will be
possible. Therefore, the WPC has introduced a marginal risk for
excessive rainfall through tonight across our Florida counties and
a flood watch is currently in effect for portions of the Florida
panhandle and western big bend. Based on the forecast for Elsa,
the system will be moving steadily northward as it passes with
most of its rainfall impacting the eastern Florida big bend where
we could easily see a couple of inches of rain.
&&
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not requested. However, spotters are always
encouraged to safely report significant weather conditions when they
occur (while following all local, state, and CDC guidelines) by
calling the office or tweeting us @NWSTallahassee.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 72 85 71 86 72 / 40 60 30 70 50
Panama City 75 85 73 86 73 / 60 50 40 60 40
Dothan 72 85 70 86 70 / 20 60 20 70 30
Albany 73 87 72 86 72 / 20 50 20 70 30
Valdosta 72 85 69 86 71 / 30 60 20 80 50
Cross City 73 87 72 85 71 / 50 50 30 70 60
Apalachicola 75 83 74 84 75 / 60 40 40 50 50
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...Flood Watch through Monday evening for Calhoun-Central Walton-
Coastal Bay-Coastal Franklin-Coastal Gulf-Inland Bay-Inland
Franklin-Inland Gulf-Liberty-South Walton-Washington.
High Rip Current Risk through late Monday night for Coastal Bay-
Coastal Gulf-South Walton.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...Haner
SHORT TERM...Barry
LONG TERM...Barry
AVIATION...Haner
MARINE...Barry
FIRE WEATHER...Barry
HYDROLOGY...Barry