Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/18/16
Area Forecast Discussion
National Weather Service Binghamton NY
1032 PM EDT Sat Sep 17 2016
.SYNOPSIS...
Showers and thunderstorms will move through central New York and
northeast Pennsylvania overnight ahead of a warm front. A cold
front will then slowly progress through the region Sunday, with
additional showers and storms at times. High pressure builds into
most of the region again by Monday night and Tuesday with fair
weather expected for the middle of next week.
&&
.NEAR TERM /THROUGH SUNDAY/...
Water vapor imagery shows a short wave moving into the eastern
Great Lake region late this evening. This feature weas supporting
a southwesterly low-level jet close to 40 knots near 850 mb. This
low-level jet was advecting moisture into NY and PA and leading to
destabilization in the presence of upper level lifting associated
with upper PV advection. The water vapor imagery was indicating
that this upper level wave was moving to the northeast and this
coincided very well with the movement of the showers and isolated
thunderstorms. Mosaic radar imagery showed most of the
precipitation will affect north central NY through 6Z with little
if any precipitation south of here. In northeast PA, it looks dry
as per radar imagery and lack of forcing at least through 8-9z.
The HRRR model is in line with this, so radically adjusted the
near term pops to reflect current radar, extrapolation,
mesoanalysis dynamics/moisture advection and the HRRR which has
the best handle on the present. Later tonight, after 09z another
small upper level wave seen in the water vapor imagery over
Indiana will press the low-level jet a little farther east. albeit
a little weaker. Based on the HRRR radar echoes reach south-
central NY and northeast PA between about 8z-12z. So have brought
the bulk of precipitation in at this time much later than previous
forecast.
Then for Sunday, there will be another southern branch wave will
advect moisture and precipitation northeast into northeast PA to
the Catskills. So have highest POPS here on Sunday. For the rest
of central NY, heating will lead to some instability so continue
chance POPs for showers and some storms as per previous shift.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
Dfclt to define fnt stull drapped over the area on Sun ngt as an
upr shrt wv aprchs from the west. Looks like the best chance for
pcpn will be over the sern zones...although the NAM seems to be
suffering from a bit of conv feedback in the tropical moist plume so
I don/t xpct that soln either. so...while deep moist avbl...weak
frcg shd limit rainfall amts. In any case upr trof and fnt will
slowly push east into Mon and slowly bring an end to the rain from
west to east.
Hipres blds in for Tue bring clrg skies. No really strong CAA in
the zonal flow so temps shd be near or slgtly abv seasonal lvls.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Broad upr trof slowly slides east in the long term allowing rdgg
sfc and aloft to slowly bld in for the rest of the work week. Rdgg
helps to push the wrm fnt well west and eventiually north of the
fcst area so despite the return waa ltl if any pcpn is xpctd to
dvlp under ther flat rdg. Aftn max temps will be abv nrml once
again but late summer Canadian hipres will the air somewhat drier
and RH`s more comfortable.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
A general lowing of CIGS tonight as an area of rain and embedded
thunder moves through the terminals. I indicated a 4 hour window
after 04Z with the best thunder chances. After the area of rain,
cigs will lower further and may result in very low cigs especially
the elevated terminals. Improvement is expected by mid morning
Sunday.
Southwest winds around 10 kts through Sunday afternoon.
OUTLOOK...
Monday...Possible restrictions early from lingering showers/lower
ceilings, especially KBGM/KAVP. Otherwise, improving conditions.
Tuesday/Wednesday...Mostly VFR. Possible early morning
restrictions from fog/lower ceilings each day.
Wednesday/Thursday...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...None.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DGM
LONG TERM...DGM
AVIATION...Heden
Area Forecast Discussion
National Weather Service State College PA
1132 PM EDT SAT SEP 17 2016
.SYNOPSIS...
A moist southerly flow ahead of a slow moving cold front will
bring occasional showers and thunderstorms through the rest of the
weekend. Rainfall totals by Monday will likely be near one inch
in many locations. Improving conditions with decreasing humidity
will occur Monday and Tuesday under high pressure. Temperatures
will again rise to well above normal levels again later in the
week.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
The most organized convection continues over NW Pa. with more
widely scattered showers extending down into the Laurel Highlands.
There is still some lightning but with instability very limited,
the threat for strong winds seems to have diminished. The biggest
threat now seems to be for locally heavy rain.
The latest HRRR shows the showery rains continuing into Sunday
with the showers becoming more numerous into central Pa later
tonight. We are embedded within a ribbon of PWATs of 1.5-2.0" so
the potential for heavy downpours will develop as the upper trough
moves east.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
Sunday`s challenges include how far SE the overnight precip gets,
and, related, where the low level boundaries might be for
convective focus. CAPEs still do not get to any level of
excitement, and the marginal dynamics of the previous evening are
all but gone. Still, a weak ripple of low pressure may move NE
through the Mid-Atlantic and bring a period of storms during the
daylight hours. We do have a fairly high confidence in most places
getting wet - esp SE of UNV. However, it looks very disorganized
when looking at the mass fields and, thus, the QPF fields as well.
This leads to a low confidence in the timing of precip. The more-
likely placement of the precip - some of which may be heavy if
training cells/clusters develop - is more certain. Maxes will
still be well above normals, but diurnal ranges will be just
10-12F.
Some drying is possible in the NW before the end of the short-term
period.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
The extended will begin with a shortwave trough that will keep the
chance of showers in the forecast Sunday night and Monday, before
high pressure brings some dry weather for Monday night and
Tuesday.
The next cold front in the pattern is destined to run into rising
heights aloft over the northeastern US Tuesday. The normally wet
GFS shows the band of showers associated with this system drying
up as it moves through the eastern Gr Lakes. The ECMWF also shows
the showers dying, but not totally as they move into the region by
late Tuesday. I used the SREF/GEFS pops which lead to a higher
confidence that the GFS will be correct keeping us dry.
The midweek through weekend timeframe will feature a rebound in
the amazingly persistent (this summer) eastern US/western
Atlantic upper ridge. The NAEFS shows anomalously high upper
heights and warm temps from Wed into the weekend. So the upcoming
week promises to be yet another warmer than normal one and
basically dry as no significant chance for rain seems to be in the
cards.
&&
.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
Cigs have bounced down for a brief moment at KJST & KBFD after a
little rain. Much of the area is VFR for the moment, and some
destabilization should occur - mainly over OH and in NW PA.
Daylight is short for really good instability to develop, but a
weak short wave trough and decent LLJet will likely sustain
convection that does develop and make it last much of the night as
it progresses to the E and slightly S. Nighttime decoupling and
the moderate LLJet will create a brief time of LLWS centered
around 06z. The high moisture and weak sfc winds could make for
IFR/LIFR cigs in the second half of the night. Some improvement is
expected Sun morning, but lots of cloud cover and ever-lowering
sun angle may not allow for a very rapid improvement. A cold front
will be oozing in from the NW later in the day, but will be ill-
defined and could take until Monday to complete the traverse
across central PA. Thus, sct SHRA/TSRA are expected on Sunday.
Some heavier storms may occur vcty KMDT/KLNS on Sunday.
Outlook...
Mon-Thur...AM valley fog poss. Otherwise, no sig wx.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...La Corte
NEAR TERM...La Corte
SHORT TERM...Dangelo
LONG TERM...La Corte
AVIATION...Dangelo
Area Forecast Discussion
National Weather Service Dodge City KS
612 PM CDT SAT SEP 17 2016
...Updated for Aviation...
.SHORT TERM...(This evening through Sunday)
Issued at 335 PM CDT Sat Sep 17 2016
Shortwave trough was moving east southeast out of southern
Wyoming and northern Colorado this afternoon. Fairly cool mid
level temperatures around -15c associated with the wave is
helping destabilize the mid levels with clusters of strong to
severe thunderstorms breaking out over northeast and east central
Colorado. Farther southwest, convection was also breaking out over
the Raton Mesa. Instability axis has been situated over eastern
Colorado and south into far southwest Kansas and down through west
Texas. Better Bulk Shear values are also confined to the TX Panhandle
with marginal shear farther north. Best chance for severe should
be over the far southwest where parameters come together better.
A little more uncertainty as to how long convection over northeast Colorado
is sustained as it moves out into northwest and north central Kansas
this evening. Most model solutions have that convection dying out this
evening while the HRRR tends to sustain it all the way through central
Kansas. Storms could stay organized across southwest into south central
Kansas this evening and may need to increase pops across that area.
Things quiet down fairly quickly after midnight as the short wave trough
moves east out of the area.
Sunday will be mainly sunny as upper level ridging begins to build over
the central Plains. With increasing thickness values and weak low
level downslope, high temperatures should be a few degrees warmer
than today, around 85 to 90.
.LONG TERM...(Sunday night through Saturday)
Issued at 335 PM CDT Sat Sep 17 2016
Upper level ridging builds across the southern CONUS during the early
part of next week with the upper level westerly flow shunted
northward into the northern Plains and southern Canada. A shortwave
moving east along the US/Canadian border on Monday will push a
cold front south into the central Plains, possibly as far south as
I-70, on Monday afternoon. With a drier airmass in place by then,
the potential for storms looks minimal. Daytime high temperatures
should be up into the 90s during the first part of the week.
By mid week. the upper high gets suppressed a little farther south while
upper level southwesterly flow increases over the central Plains.
A shortwave lifts out over the central Plains on Wednesday. There
is some potential for perhaps some nocturnal storms across western
Kansas early Wednesday morning. This wave could push a boundary
into western Kansas during the day, providing focus for more
additional storm development. Temperatures should be cooling off
back into the 80s later in the week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 609 PM CDT Sat Sep 17 2016
A strong shortwave trough will move across the Central Plains
tonight with scattered thunderstorms before 06Z. Southeast winds
will become southwesterly after 12-15Z. VFR conditions are
expected.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 58 87 60 93 / 30 0 0 0
GCK 55 87 56 91 / 40 0 0 0
EHA 55 88 57 92 / 40 0 0 0
LBL 57 89 59 92 / 40 0 0 0
HYS 57 87 60 91 / 30 0 0 0
P28 60 86 65 93 / 30 10 0 0
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Gerard
LONG TERM...Gerard
AVIATION...Kruse
Area Forecast Discussion
National Weather Service Wilmington NC
1118 PM EDT Sat Sep 17 2016
.SYNOPSIS...
Tropical Depression Julia will continue to meander off the coast,
possibly degrading to a remnant low tonight or Sunday. Mid-level
low pressure will once again develop across the southeast states next
week possibly keeping showers in the forecast with mild temperatures
continuing.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
As of 1100 PM Saturday...Water levels were still dropping at the
beaches with the passage of high tide there a few hours ago.
Portions of the lower Cape Fear River were just at high tide and
will be falling there as well through midnight. We expect
elevated water levels at the time of high tide through Monday due
to persistent onshore flow and high astronomical tides.
Tropical Depression Julia may degrade to a remnant low by Sunday
morning as it drifts NW and N. Meanwhile, a weak cold front will
approach the Appalachians overnight as ridging draped over the
north and west side of Julia maintains its hold on the eastern
Carolinas.
The HRRR model is showing isolated light showers across the waters
overnight. These showers will struggle to reach the beaches before
dissipating. Otherwise, like last night, expect low stratus to
envelop the area after midnight. Model consensus has overnight
lows in the low to mid 70s.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
As of 315 PM Saturday...Tropical Depression Julia will have
transitioned to an extra-tropical system according to the latest NHC
advisory. Julia is projected to drift north while gradually
weakening, ultimately merging with a frontal system that will move
offshore on Monday. The increasing proximity of Julia`s remnants in
combination with the cold frontal passage could bring scattered
convection to the forecast area on both days. Although deeper
moisture will move in on Monday, given the strength of both
systems do not think that excessive rainfall will be a concern.
High temperatures will recover back around to above seasonal norms,
with mid 80 to upper 80s and lows in the lower to mid 70s on both
days.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 315 PM Saturday...Medium range guidance has trended to a more
unsettled solution but unsettled may be overstating it a bit as
it certainly won`t be a washout. Mid level low pressure should
cutoff along the southeast coast early in the workweek and meander
about before retrograding to the northwest and basically washing
out. There is very little indication of this feature at the
surface with a weak coastal trough at best. The GFS is more robust
with the qpf fields as opposed to the ECMWF but it appears the
ECMWF may be playing catch up. Overall I did increase the pops
incrementally along with the cloud cover for most of the period.
Temperature forecast is still on the warm side especially compared
to the MEX and if trends continue they to will need to be adjusted
downward.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
As of 00Z...Meandering low pressure offshore will give us an
isolated chance of a shower overnight. Models are in fairly good
agreement with introducing stratus overnight at all locations.
Some reduction in visibilities is possible, however confidence is
rather low on the severity. A continued chance for isolated
convection in the morning with weak convergence boundaries pushing
ashore. Mainly easterly flow.
EXTENDED OUTLOOK...Low chance for convection through Monday with
the remnants of Julia and a dissipating stationary front. Brief
IFR conditions possible during the pre-dawn hours each day from
either low stratus or reduced vsby from fog. By Tuesday, a cold
front will shift across the TAF sites with predominate VFR
conditions to follow.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
As of 1100 PM Saturday...Small Craft Should Exercise Caution
conditions are expected to persist into early Sunday morning. Seas
will be 5 ft or 4 to 5 ft. The pressure gradient between northward
drifting Tropical Depression Julia and an expansive high to our N
will result in NE winds of 10 to 15 kt with gusts to 20 kt possible.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 315 PM Saturday...Tropical Depression Julia may transition
to will have transition to a remnant low by/during this period of
the forecast. Julia is projected to drift north while gradually
weakening, ultimately merging with a frontal system that will move
offshore on Monday. Expect highest seas of 3 to 5 ft on Sunday,
gradually decreasing through the short term as Julia loses
strength and definition. Winds over the short term will stay in
the 10 to 15 kt range.
LONG TERM /TUESDAY THROUGH THURSDAY/...
As of 315 PM Saturday...A lingering front/trough offshore and weak
high pressure over the Ohio Valley will keep synoptic winds from the
northeast through the period. Neither feature is overly impressive
so wind speeds in the lower end of a 10-15 knot range can be
expected. Significant seas of 2-3 feet should prevail throughout the
period.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.
&&
$$
NEAR TERM...RJD
SHORT TERM...REK
LONG TERM...SHK
AVIATION...DL
Area Forecast Discussion
National Weather Service Paducah KY
614 PM CDT SAT SEP 17 2016
.UPDATE...
Updated aviation section for 00z taf issuance
&&
.SHORT TERM...(Tonight through Monday night)
Issued at 241 PM CDT Sat Sep 17 2016
Radar pretty quiet. Only spotty light rain/showers since mid
morning. Little activity currently. Will maintain a very low
chance PoP into the early evening over the east 2/3 of the area.
RAP shows limited elevated instability, thus will keep slight
chance TSRA. But overall, not much expected.
Next system will be a s/wv moving from the central Plains to the
TN Valley Sunday/Sunday evening. Most of the moisture stays to our
south, so dry forecast for now. Dry weather will continue Sunday
night through Monday night as well. In the wake of the s/wv, weak
high pressure will be in control.
Temps will be a blend a MOS blend. We will monitor the fog potential
overnight. It is in the forecast. Lows should cross over most areas.
Could be low clouds as well.
.LONG TERM...(Tuesday through Saturday)
Issued at 241 PM CDT Sat Sep 17 2016
Upper level ridge is in place from Wednesday into Friday. On Friday
heights fall slightly on all models as upper level low forms over
the northern Rockies. By 18z Saturday, the upper level low moves
into the northern plains with the GFS having a more negative tilt
than other models and ensembles and thus much faster with the cold
front.
More interesting to us is the moisture pattern forecast. Moisture
off the southeast coast early Tuesday is forecast to move under the
ridge toward the west and northwest. Although models vary on the
details including timing, it looks like the best chance for
precipitation will be on Saturday.
With the ridge over the area, expect temperatures to be well above
normal at least until Friday. Normal highs are in the lower 80s,
expect to see upper 80s to lower 90s during that time.
&&
.AVIATION...
Issued at 614 PM CDT Sat Sep 17 2016
Last visible satellite pictures of the day indicate cumulus clouds
are melting away quickly as sunset approaches. Surface winds are
light and variable already. The combination of clear skies and light
winds raises the likelihood of ground fog overnight. Dew points were
around 70 degrees at 23z, and the ground is rather moist from last
nights rainfall. Given all these factors, ifr vsbys are expected
late tonight into early Sunday morning. The fog will burn off Sunday
morning, followed by a period of broken stratus or stratocu. This
cloudiness will mix out during the midday hours, followed by mainly
clear skies.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
AVIATION...MY
Area Forecast Discussion
National Weather Service Blacksburg VA
917 PM EDT Sat Sep 17 2016
.SYNOPSIS...
High pressure will continue to linger across the region overnight
into Sunday morning. A slow moving cold front will approach from
the west Sunday, reaching the western mountains Sunday evening.
The front should finally cross the region Sunday night into early
Monday followed by high pressure for Tuesday through Thursday.
&&
.NEAR TERM /THROUGH SUNDAY/...
As of 900 PM EDT Saturday...
Band of showers to the west associated with the tail of the
passing wave to the north continues to edge slowly east-northeast
toward the far northwest counties this evening. Latest HRRR does
attempt to push some of these light showers or sprinkles into the
West Virginia counties between now and midnight before fading upon
encountering dry air aloft as seen via evening soundings. Thus may
add in a low end pop along the northwest slopes for a few hours
given weak moisture convergence, and then cut after midnight as
this wave lifts out and added showers reform farther west closer
to the actual surface front overnight. Otherwise mainly cloudy far
northwest sections with clear skies to initialize elsewhere before
possibly seeing more low clouds/fog redevelop espcly east of the
Blue Ridge late. Think any added showers late tonight with the
pre- frontal band to stay to the west per latest slower model
solutions. Therefore keeping things basically dry early Sunday
across northwest sections after current showers fade. Lows again
mostly in the 60s with a few 50s deeper valleys pending the degree
of clouds and patchy fog late.
Previous discussion as of 330 PM EDT Saturday...
The wedge broke across the mountains by noon and then across the
piedmont by 300 pm. Low morning stratus clouds lifted to become fair
weather cumulus as the wedge broke. A subsidence inversion may
redevelop across Southside this evening to bring some low clouds
back in, but as mixing increases with an approaching cold front,
these clouds should dissipate through the early morning hours.
Showers to the west with a leading trough are making slow progress
to the east this afternoon. Models have this trough stalling across
the Tennessee and Ohio Valleys this evening. A deepening upper level
trough will swing over the Mississippi Valley tonight, pushing a
cold front east into the Ohio Valley. This front will catch the
stalled trough early Sunday morning, then slowly track over the
mountains through the day Sunday. Clouds will increase east of the
Blue Ridge but do not expect showers to move much past the foothills
tomorrow afternoon.
With the slow advance of rain into the region, tweaked temperatures
up a few degrees, especially across the piedmont. Afternoon highs
will range from the mid to upper 70s west to the mid to upper 80s
east.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
As of 355 PM EDT Saturday...
500 MB upper trof will be moving across the eastern United States in
two pieces. The northern part of the trof will be near the New
England coast by late Monday while the southern end is moving slower
and will just be crossing the central and southern Appalachians.
Best synoptic scale forcing will be Sunday night when the right rear
quadrant of the upper jet crosses Virginia and when the low level
convergence is maximized along the front. Temperatures aloft will
also be cooler on Monday which will enhance the instability. Will be
leaning toward the timing of the GFS for the wind shift with the
front and timing of the end of the precipitation from west to east
on Monday. Not much of a change in air mass behind the front. Models
showed only a minimal drop in 850MB temperatures.
Western edge of the deeper moisture is just exiting the forecast area
on Monday evening. Deep northeast winds that set up behind the front
and north of the tropical cyclone over the southeast United States
may keep cloud cover in the piedmont through Tuesday. A secondary
cold front will approach the area from the northwest on Tuesday.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 200 PM EDT Saturday...
Not much moisture along the cold front which will weaken as it moves
east Tuesday night. Surface high pressure over the Ohio Valley will
move east into Pennsylvania and New York by Thursday morning. A
strong wedge will develop along the east slopes of the Appalachians
Wednesday night and Thursday. High pressure will than remain over
the region for the rest of the week. Have cooled down temperature a
couple of degrees below guidance for Wednesday night through
Thursday night in the wedge. By Saturday there may be enough
moisture and southeast upslope winds for some precipitation on
Saturday. This will be the only period after Tuesday with a
probability of precipitation.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
As of 700 PM EDT Saturday...
VFR will prevail this evening under mid deck cigs over parts of
the mountains and scattered strato-cumulus elsewhere. Few light
showers may approach the KBLF/KLWB vicinity in the next few hours
but expecting them to dissipate so not including mention. Main
question overnight is whether or not the residual wedge will
redevelop espcly eastern sections late. Latest models including
Bufkit soundings indicate potential for stratus/fog at KLYH and
KDAN late with patchy fog even possible back to KBCB. This remains
a bit uncertain, but given clear skies will include a period of
MVFR to IFR across the east by daybreak, and patchy fog in the
western valleys including KBCB, with KLWB perhaps staying under
enough clouds to preclude much fog.
May take until mid/late morning for possible sub-VFR conditions to
clear the east with deeper moisture slowly invading the west
through the afternoon with the front. These lower conditions will
begin across the mountains by Sunday afternoon...then eventually
spread east by the late afternoon/evening hours. However given
slower trends off latest models, will delay any rainfall at
KBLF/KLWB until afternoon and include a VCTS mention within
prevailing MVFR showers later in the afternoon. Will also edge
showers east to KBCB but leave out of KROA and points east during
the valid taf period.
Extended aviation discussion...
Cold front will move east into the region Sunday night, but take
until Monday to move completely east of the CWA. Sub- VFR cigs
will be possible Sunday night as a result of increasing showers
and isolated thunderstorms mainly during the evening.
High pressure will build back into the region early in the week,
so after the front exits the area Monday morning, expect most VFR
conditions for several days until late week. The exception will be
late night/early morning fog/low clouds, more likely toward the
end of the week as moisture begins to return around the departing
surface high.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...AMS/JH
NEAR TERM...JH/RCS
SHORT TERM...AMS
LONG TERM...AMS/RCS
AVIATION...JH/RCS
Area Forecast Discussion
National Weather Service Shreveport LA
945 PM CDT SAT SEP 17 2016
.DISCUSSION...
While the sct convection has diminished earlier this evening over
extreme NE TX/SW AR...another complex of convection that developed
earlier this afternoon over Cntrl OK has raced SE across extreme SE
OK and about to enter SW AR...along a weak shortwave well ahead of an
upper trough noted on the water vapor imagery extending from the Cntrl
Plains SW into the Rockies. The air mass remains moderately unstable
across extreme NE TX/SW AR...with the convection primarily outflow
driven. The short term progs did not initialize well at all on this
area of convection...with the HRRR having to play catchup on the
current trends and depicting the convection eventually weakening by
06Z over SW AR with the loss of instability N of a remnant low level
theta-e bndry along the AR/LA line and extending W into the I-30
corridor of NE TX where convection developed earlier today.
Have updated the forecast to raise pops to high chance through 06Z for
SE OK/adjacent sections of SW AR...and tapered pops down to mid and
low chance for extreme NE TX/the remainder of SW AR. Did taper pops
back to slight chance after 06Z with the convection expected to
diminish with the shortwave passage well NNE of the area. The
remainder of the night should be quiet...as we await the
aforementioned upper trough passage after daybreak Sunday morning
which should drive the ongoing convection over the TX/OK Panhandles
which should accelerate SE into SE OK around 12Z. This convection
should build SE across much of NE TX/SW AR Sunday morning...and across
the remainder of E TX/N LA/Scntrl AR by afternoon. Have expanded mid
to high chance pops across much of the region Sunday per the
consistent 18Z/00Z NAM and new runs of the HRRR. Did tweak min temps
tonight down a degree or two per the current trends and potential for
cooler outflow winds.
Zone update already out...grids will be available shortly.
15
&&
.PREV DISCUSSION... /issued 743 PM CDT SAT SEP 17 2016/
AVIATION...
For the 18/00Z TAFs, VFR conditions prevail at all terminal sites
this evening as convection continues to slowly diminish across the
region. Have left VCTS in for the first few hours of the period at
TXK/ELD as showers and storms continue to develop along a frontal
boundary nearing the I-30 corridor. This front may make additional
southward progress tonight as fast-moving upper level shortwave
advances southeast toward the Red River Valley. This upper trough
may allow additional convection to affect the TXK terminal closer
to 18/06Z but have left any TS mention out for the time being. A
more broad scale trough over the TX/OK panhandle region will also
shift east across the northern half of our region on Sunday so a
better chance of showers and storms may come during the latter
half of the TAF period. For now, have only added this possibility
at TXK/ELD where confidence is higher but may need to include the
I-20 terminals as well for late Sunday morning through afternoon
as this trough shifts overhead. Winds will continue to be light
and mostly variable as the surface boundary lingers, and this will
likely lead to another round of fog around daybreak with patchy
low cigs also possible. MVFR/IFR conditions will only be a concern
during the mid to late morning hours on Sunday. Higher wind speeds
and gusts will be associated with any convection in and around the
terminal sites, mainly after 18/15Z. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 74 93 73 97 / 5 40 10 10
MLU 73 92 72 95 / 5 50 10 10
DEQ 70 88 68 93 / 50 50 10 10
TXK 71 89 70 94 / 30 50 10 10
ELD 71 89 70 93 / 20 50 10 10
TYR 75 92 73 96 / 5 30 10 10
GGG 73 92 72 96 / 5 30 10 10
LFK 73 94 74 96 / 5 30 10 10
&&
.SHV Watches/Warnings/Advisories...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
15
Area Forecast Discussion
National Weather Service Albany NY
436 AM EDT SUN SEP 18 2016
.SYNOPSIS...
A cold front will slowly move towards the region from
the eastern Great Lakes and southeast Canada today with showers and
some thunderstorms. A disturbance will move along the front for an
extended period of rainfall tonight into Monday. The front moves
east and weakens Monday night into Tuesday...as drier air filters
in but temperatures will still be above normal.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 435 AM EDT...An upper level disturbance and a prefrontal
sfc trough continue to focus showers and a few elevated
thunderstorms north and west of the Capital Region...and mid-
Hudson Valley this morning. The latest NAM/GFS continue to
indicate Showalter stability index values of 0 to -2C especially
from Albany south this morning...so we will keep a slight chc of
thunderstorms in the forecast. The showers have been mainly north
and west of the Capital Region early on due to those locations
being near the right entrance region of a 90+ kt jet streak with
good upper level divergence over northern and central NY. Some
much needed rainfall will move into the southern half of the
forecast area late this morning. Humidity levels and PWAT values
will be on the increase.
A brief lull in the pcpn is likely...but then along the southern
periphery of the sfc trough some isolated to scattered showers
and thunderstorms may rekindle. The latest HRRR is hinting at this
possibility too. SBCAPE values are generally in the 500-1000 J/kg
range on both the NAM/GFS with some slightly higher pockets
possible in the mid-Hudson Valley and NW CT. The deep shear is
not especially strong with 25-30 kts with mid level lapse rates in
the 6-6.5 C/km range. The limited instability and heating should
keep any thunderstorms from being severe...but if higher values of
instability are realized...then a rogue one or two could be
possible with some strong winds.
Highs today will generally be in the 75-80F range in the valley
areas...and over the hilltowns...with upper 60s to lower 70s over
the mountains. Humidity levels will be on the sticky side with
dewpts rising into the 60s.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
Tonight...The cold front makes very slow progress eastward...and
a mid-level disturbance moves north-northeast from eastern TN and
Piedmont area. A plume of higher PWAT air will continue to be over
the region with values of 1.5-2.0" which are 1-3 standard
deviations above normal with the higher values from the Taconics
eastward into western New England. Showers with isolated to
scattered thunderstorms will evolve into a rainband or rainshield
ahead of the front. Periods of moderate to occasionally heavy rain
is possible overnight...especially from the Capital Region...and
eastern Catskills south and east. The highest POPS were included
here. Lows will be on the muggy side with mid and upper 60s from
the Tri Cities south and east...and upper 50s to lower 60s north
and west.
Monday...The mid and upper level flow from the S to SW to the N to
NE continues to be parallel to the sfc front which will continue
the threat of rain...especially in the morning. Some clearing over
the northwest portion of the forecast area is possible in the
afternoon. The above normal PWATS and better H850 theta-e
gradient continue to be over the southeastern portion of the ALY
forecast area. A gray and humid start to the week is likely with
period of showers and a chance of thunderstorms. The instability
looks even less on MON...especially from the GFS with SBCAPES of
250-500 J/kg. The antecedent conditions are dry leading up to this
multiple day event...but some ponding of water on roadways and
poor drainage flooding of low-laying areas may be possible Monday
morning into the afternoon. Highs will mainly be in the mid and
upper 70s with some cooler readings over the mountains /upper 60s
to lower 70s once again/.
Monday night...The front finally make some steady progress across
New England with isolated to scattered showers ending over the mid
Hudson Valley and NW CT early in the evening. The boundary may
actually fall apart with a weakening thermal gradient. Dewpts
fall in the 50s to lower 60s with some clearing skies. In the weak
cold advection regime lows fall back into the mid 50s to lower
60s.
Tue-Tue night...A secondary cold front...and the upper trough axis
approaches and dampens out during the day. Isolated showers are
possible north and west of the Capital Region. More sunshine will
allow temps to be at least 10 degrees above normal with the latest
GEFS having H850 temps 1 to 2 standard deviations above normal
with /+12C to +15C range/ with highs in the upper 70s to lower 80s
in the valleys...and lower to mid 70s over the higher terrain.
High pressure begins to ridge in from the Midwest and lower Great
Lakes Region with lows generally in the 50s with some upper 40s
over the southern Adirondacks.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Guidance is in good overall agreement with the longwave pattern.
Mid week have a fast zonal flow along the United States-Canadian
border on the southern periphery of an upper low over Hudson`s Bay.
As we head into the latter part of the week a large upper low
develops over the western United States with a sharp narrow ridge
forming between the lows.
For our area looking at mainly fair and dry weather. The only chances
for rainfall are expected with a backdoor front which should move
southward across the region early in the weekend. Temperatures are
expected to remain above normal by 5 to 10 degrees until the backdoor
front moves through ushering a more seasonable airmass in.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
Showers associated with a pre-frontal trough and approaching short
wave continue to move across the area and are expected to do so
through the early morning hours. Overall conditions are expected
to lower to MVFR with showers then linger through much of the morning.
After these showers move off a bit of a lull is then expected.
With the help of daytime and a humid airmass in place and the approach
of a stronger short wave storms are expected to develop with a focus
more to to the south and east of the Capital District. Overall chances
for the storms will increase as we head through the nighttime hours as
the approaching cold front move into the region.
A return to VFR conditions are expected by afternoon, however any storm
impacting a site will result in MVFR and possibly brief IFR conditions.
Conditions are expected to lower back down to MVFR with increasing chances
for showers tonight.
Southerly flow continues with the strongest winds at KALB as the flow gets
enhanced by the Hudson River Valley. Have keep gusts in at KALB through
the early morning hours.
Outlook...
Monday Night: No Operational Impact. NO SIG WX.
Tuesday: No Operational Impact. NO SIG WX.
Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: No Operational Impact. NO SIG WX.
Wednesday Night: No Operational Impact. NO SIG WX.
Thursday: No Operational Impact. NO SIG WX.
&&
.FIRE WEATHER...
A cold front will slowly move towards the region from
the eastern Great Lakes and southeast Canada today with showers and
some thunderstorms. A disturbance will move along the front for an
extended period of rainfall tonight into Monday.
Humidity levels will be high the next few days with 60 to 75
percent readings this afternoon and Monday afternoon...and 90 to
100 percent readings tonight.
A widespread wetting rain is likely the next 36 hours with 1 to
1.5 inches possible.
The winds will be southerly today at 10 to 15 mph...and then will
lighten to less than 10 mph tonight into Monday.
&&
.HYDROLOGY...
No widespread hydro problems are expected the next 5 days ending
on Thursday.
Some beneficial rainfall is expected over the hydro service area
/HSA/ today through Monday. A slow moving cold front and multiple
disturbances moving along or ahead of it will bring one to one and
half inches of rain to the HSA...with some locally higher amounts.
The higher totals will likely be south and east of the Capital
Region.
The system will tap into tropical moisture from the Gulf of
Mexico with precipitable water levels increasing to over 1.5
inches ahead of the cold front. Some isolated to scattered
thunderstorms are possible today and tomorrow. Some of the
downpours from the convection may yield ponding of water and poor
drainage flooding of low lying areas.
Drier weather returns by Tuesday...and may continue through the
mid week.
The U.S. Drought Monitor was released on September 15th and shows
drought conditions have worsened across portions of the Northeastern
United States as much of the region experienced above-normal
temperatures and below-normal precipitation. A (local) Drought
Information Statement was issued this past Friday evening
(ALBDGTALY).
For details on specific area rivers and lakes, including observed
and forecast river stages and lake elevations, please visit the
Advanced Hydrologic Prediction Service /AHPS/ graphs on our
website.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...SND/Wasula
NEAR TERM...Wasula
SHORT TERM...Wasula
LONG TERM...IAA
AVIATION...IAA
FIRE WEATHER...BGM/Wasula
HYDROLOGY...BGM/Wasula
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
340 AM CDT Sun Sep 18 2016
.Discussion...
Issued at 339 AM CDT SUN SEP 18 2016
Water vapor showing a compact upper shortwave trough moving through
central Kansas this morning with radar trends depicting isolated
convection associated with this feature well to our west. Prevailing
thought out of the gate is that much of this activity will dissipate
with further eastward progress this morning...however a light
sprinkle cannot be ruled out for northeast Kansas and far northwest
Missouri per the latest HRRR runs. Despite this...activity looks
pretty anemic on TWX radar and will hold off on any precip mention
unless trends in the next few hours suggest otherwise. Aside from
some early morning cloud cover...today is shaping up to be a
beautiful late September day with well above normal temperatures as
highs climb into the lower to middle 80s. 850 temps this afternoon
will be a few degrees warmer than yesterday by 00z as southerly flow
returns following the passage of a weak warm front this afternoon.
This will mark the beginnings of a fairly decent warming trend as
highs on Monday flirt with the 90s degree mark out ahead of a weak
cold front that will be sagging south through Iowa throughout the
day. In terms of sensible weather impacts...latest model runs have
backed off on precip chances for the lower Missouri Vly Monday
afternoon as convergence into the aforementioned front remains weak
at best. The next chance for organized shwr/storm activity looks to
hold off until Tuesday night/early Wednesday models suggest an MCS
may clip northern portions of the fcst area during the early morning
hours...although its likely many areas will remain dry with lack of
any substantial midlevel forcing. Otherwise the remainder of the
work week looks dry with above average temperatures continuing. Big
changes finally look to be in store for the weekend as a strong
longwave trough and associated cold front move through the region
Saturday night/early Sunday. This should result in renewed precip
chances and cooler temps late in the forecast period.
&&
.Aviation...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1209 AM CDT SUN SEP 18 2016
Expect VFR conditions through the forecast period. Still a very low
end chance for brief fog at the terminals, but with confidence and
probability so low, decided to remove the mention of fog.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...None.
MO...None.
&&
$$
Discussion...32
Aviation...Leighton
Area Forecast Discussion
National Weather Service Fort Worth TX
334 AM CDT SUN SEP 18 2016
.DISCUSSION...
Two distinct areas of convection are ongoing across the state of
Texas early this morning. The first is a rapidly decaying area of
showers and a few lingering storms near San Angelo which are part
of a storm complex that developed this evening. The only impacts
from these convective remnants on our CWA will be a dense canopy
of mid and high-level clouds which should continue to thin through
the morning hours.
The second and more robust area of storms is a southeastward-
surging MCS which currently stretches from near Childress,
northeastward towards Oklahoma City. Latest RAP-based objective
analysis from the SPC reveals this complex presently exists within
a local minimum in instability, a result of earlier convection
across central and southern Oklahoma. Recent radar trends suggest
that the southern end of the MCS is beginning to build southward--
right down the backward/upwind propagating Corfidi Vector--along
a west-to-east oriented 925-850 mb theta-e gradient situated near
the Red River. As this complex and its associated outflow continue
to move southward into a somewhat more favorable thermodynamic
environment, it`s possible we see renewed convective development
into roughly the northeastern third of our CWA. Recent time-lagged
runs of the HRRR seem to be (within about an hour or two)
capturing the evolution of this MCS fairly well. Aside from some
temporal adjustments to speed up this system`s progression, I`m
hard pressed to find reasons to ignore its consistent forecast
signal.
Based on a combination of radar trends and high-resolution
guidance, expect strong gusty outflow winds to arrive across our
northwestern Counties (Young, Jack, Montague) shortly, around 4
AM, into the Metroplex around 6 AM, and then exiting our eastern
zones in the 9-11 AM time frame. While I can`t rule out the
potential for a marginal severe gust mainly our northern row of
counties, in general, anticipate gusts into the 40-50 mph range
across the northwestern counties, with a gradual decrease in gust
intensity as the outflow and storms press southeastward. Expect
showers and storms to follow behind the outflow boundary, building
southward towards the Metroplex and potentially even a few rows of
counties to the south and east later this morning.
Once this batch of convection clears the region during the mid to
late morning hours, things should quiet down with just a few
lingering showers. For this afternoon, convective coverage should
be minimal as our atmosphere will have become significantly
overturned--at least across the northwestern 2/3rds of the CWA.
Opted to leave in a low 20% PoP even in the northwest today as
earlier guidance suggested the atmosphere might recover enough to
support some isolated activity. Based on trends later this
morning, the day shift may be able to remove PoPs across a portion
of our western and northwestern CWA.
A dry stretch of weather is then in store for this coming week as
high pressure builds in overhead. High temperatures tomorrow will
get a noticeable boost into the mid and upper 90s. As we don`t
really scour out the lower-level moisture, heat index values
Monday will likely rise into the 100-104 degree range for many of
us during peak heating. Dewpoints will fall steadily, however, as
we get into the middle of next week. The next real shot of
precipitation looks to occur next Saturday as moisture returns
from the south.
Carlaw
&&
.AVIATION...
/ISSUED 1202 AM CDT SUN SEP 18 2016/
/06Z TAFs/
Concerns...wind direction and convective chances.
Changes in wind direction through the valid TAF period are likely
to impact airport flow operations despite wind speeds below 5-10
kts. Have done my best to indicate which direction will likely
prevail but confidence is low to moderate.
DFW Metroplex airports...an outflow boundary from convection
earlier in Oklahoma is swiftly moving south and may result in
north or northeast winds by 06Z. Overnight, the winds are
expected to become southerly and then southwesterly as a storm
complex approaches from the northwest. This decaying storm
complex could impact the airports between 11-15Z resulting in
north winds. We will continue to monitor the evolution of this
complex, currently in the Texas Panhandle, and adjust the TAF as
needed including changes in timing or possibly the removal of
VCTS. A return of south winds is expected by Sunday afternoon with
VFR prevailing through the end of the valid TAF period.
KACT...Southeast to southwest winds are expected to prevail
through the period. A complex of storms moving into North Texas
overnight could send an outflow boundary as far south as Waco
which may result in a wind shift to the north for a brief period.
The best chance of this wind shift would be around midday. There
is a chance isolated showers may develop around KACT in the
afternoon hours, especially if a remnant outflow boundary is near.
Will continue with a VCSH mention between 20-00Z, but this may be
removed with later TAF issuances depending on the location of the
boundary.
JLDunn
&&
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 92 76 97 76 96 / 40 5 5 5 5
Waco 95 75 97 73 96 / 20 5 10 5 5
Paris 87 72 95 71 94 / 60 5 5 5 5
Denton 90 73 96 73 95 / 40 5 5 5 5
McKinney 91 73 96 72 95 / 50 5 5 5 5
Dallas 93 77 98 77 97 / 50 5 5 5 5
Terrell 93 74 96 74 95 / 60 5 5 5 5
Corsicana 94 75 96 75 95 / 40 5 10 5 5
Temple 95 74 96 73 95 / 20 5 10 5 5
Mineral Wells 93 72 97 71 95 / 30 5 5 5 5
&&
.FWD Watches/Warnings/Advisories...
None.
&&
$$
79/90
Area Forecast Discussion
National Weather Service Grand Rapids MI
329 AM EDT SUN SEP 18 2016
LATEST UPDATE...
Synopsis/Short Term/Long Term/Marine
.SYNOPSIS...
Issued at 329 AM EDT Sun Sep 18 2016
A high pressure ridge will cross Michigan today bringing
mostly sunny skies and highs in the 70s. A weak warm front will
cross the area tonight but have little impact on our actually
weather. A cold front will then push southeast into our area later
Monday bringing the threat of a few thunderstorms late in the day
or during the evening. Most locations around the area should stay
dry and not see these storms. Temperatures overall will remain
above normal through most of this coming week.
&&
.SHORT TERM...(Today through Tuesday)
Issued at 329 AM EDT Sun Sep 18 2016
The short term looks rather uneventful for the most part. There is
a remote chance of thunderstorm today then a slightly higher risk
for thunderstorms Monday afternoon into Monday evening.
The passage of an upper level trough through the area today may
result in an isolated thunderstorm (as shown by the HRRR and RAP
models for several runs in a row) but my thing is the air is so
dry at mid levels it is hard to imagine any storm really being
able to develop.
Tonight a warm front pushes through the area but the dynamics for
that are all north of our area and once again the mid level
moisture is lacking. Also the instability is lacking...there is a
slight amount of cape in the 700 to 600 mb range late tonight...
but given the amount of dry air it would be hard to form anything.
On Monday we have a cold front heading this way but the core of a
125 to 135 knot polar jet core is forecast to move largely east
along the Canadian boarder Monday into Tuesday. That puts
southwest Michigan in the right exit region of the jet...which is
hugely not favorable for convection (which is why mid levels are
so dry Monday into Monday night). Also due to this strong jet the
low level jet core max is well north of this area putting
southwest Michigan in a speed divergence area of the low level
jet...also a good event killer. There is elevated cape Monday
evening but with the dry air and other thing not being all that
favorable I remain unimpressed. Even so the latest SPC outlook
does show a marginal risk... I agree it is marginal. The SPC SREF
from 21z shows only a 5 pct chance of even seeing a thunderstorms
west of US-131 between 4 pm and 10 pm.
Beyond that...once the cold front is through we are in dry air so
jet educed subsidence so skies should be clear to mostly clear
Tuesday.
.LONG TERM...(Tuesday night through Saturday)
Issued at 329 AM EDT Sun Sep 18 2016
A fairly mild long term period is expected with highs 75-80. Zonal
flow aloft will push low pressure over the Plains east toward
Wisconsin by Wednesday night. The cold front associated with this
low will become oriented northeast to southwest from northern Lower
to near Kansas City. That`ll allow moisture to begin to pool along
it. As the front begins to move across the cwa Thursday,
precipitable water values increase to 1.75 inches. A few
showers/storms seems like a good bet with the best chance over the
northwest cwa and a couple of those could produce heavy rainfall.
The gfs and ecmwf differ a bit with the front in that the gfs pushes
the front through the cwa, but the ecmwf stalls it out and then
pushes it back north Friday ngiht. Given the overall flatness of the
upper pattern, the ecmwf seems like a better solution. Thus we/ll
keep low chc pops in the forecast through Saturday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1241 AM EDT Sun Sep 18 2016
Skies are mostly clear and dewpoint depressions are only 1 or 2
degrees. The potential for at least patchy MVFR fog is there after
08z through 13z or so.
&&
.MARINE...
Issued at 329 AM EDT Sun Sep 18 2016
Really today would be a good day for the beach given the
sunshine... pleasant temperatures and light winds. However on
Monday that frontal system heads this way. That increases the
winds and we will likely need a small craft advisory for Monday
during the day for locations north of Holland.
&&
.HYDROLOGY...
Issued at 1247 PM EDT Sat Sep 17 2016
A broad area of rainfall developed overnight, resulting in general
rainfall totals of 0.25-0.50 of an inch. Locally higher amounts of
around 1 inch were observed, especially in a thin stretch from far
Southwest Lower Michigan northeastward through the thumb region.
River rises are expected or already occurring. Most locations
will remain well within banks. The one area with any greater
concern is Holt, where level may peak near or slightly above
bankfull. No advisories were issued for now, but may be needed in
the event that observations continue to show steep rises.
Most locations will stabilize over the next 24-48 hours with
little additional rainfall expected over the weekend. Further
rainfall activity should hold off until Monday night. Concerns for
flooding are still minimal, as drier conditions (overall) are
anticipated.
&&
.GRR Watches/Warnings/Advisories...
MI...None.
LM...None.
&&
$$
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...99
AVIATION...04
HYDROLOGY...JAM
MARINE...WDM
Area Forecast Discussion
National Weather Service Miami FL
425 AM EDT SUN SEP 18 2016
SYNOPSIS...Today, high pressure centered over the eastern Gulf
will continue the light flow and afternoon diurnally driven
convection over South Florida. The highest concentration
afternoon, diurnally driven, thunderstorms will be over the
interior. Temperatures are forecast to be near normal for this
time of year. An increase in moisture Monday through Wednesday
will lead to higher storm chances across the entire area.
.DISCUSSION...
Early this morning, IR satellite imagery indicated an
active area of convection associated with dieing Tropical Depression
Julia, still a few hundred miles east of Jacksonville. Mostly clear
skies were observed over mainland Southern Florida with a few blips
of heavier showers sitting stagnant over the Gulf waters. Last
nights 00Z MFL sounding depicted light and variable wind winds from
the surface to 400 mb, dry air in the mid and upper levels, and a
relatively thin CAPE profile throughout the sampled atmospheric
column. The high pressure axis will shift west of Florida today,
allowing for more northerly/northeasterly winds aloft along with a
slight increase in moisture in the lower levels. Both the Atlantic
and Gulf sea breeze fronts are expected to make an appearance later
this afternoon. Along these fronts, the HRRR and Hi-Res WRF models
project more coverage of showers and thunderstorms than the last
couple of days. Even portions of the east coast metro will have an
elevated chance of thunderstorms late this morning into the
afternoon. However, warm 500 mb temps (around -5.5 C) and a rather
unimpressive CAPE profile should keep the severe threat at bay. As
more moisture edges into the area from the north tonight through
Wednesday, shower and thunderstorm activity will remain elevated.
Have maintained chance pops along the coasts and likely over the
interior during each afternoon. The last few runs of the GFS have
latched on to a vort max advecting southward Monday night into
Tuesday. If this feature materializes, it could also act to trigger
nocturnal storms during this period.
Thursday through Friday, a summerlike weather pattern will return to
South Florida with southeast flow developing. The highest
concentration of afternoon and evening showers and storms will be
over the interior and Gulf Coast region with temperatures near
normal for this time of year.
&&
.MARINE...
Outside of local sea breeze effects, winds will generally be east to
southeasterly at 10 knots or less over the next few days. Isolated
to scattered showers and thunderstorms will be possible each day
with locally erratic winds and hazardous seas in and around
thunderstorms. Seas are expected to be 3 feet or less through mid
week.
&&
.AVIATION...
VFR conditions will continue at all terminals through the
late morning hours. Another round of VCTS with scattered thunderstorms
developing around the terminals is expected this afternoon, with
possible periods of MVFR conditions under lowering cigs and
reduced vis during heavy downpours. VFR should then return in the
evening hours for the Atlantic terminals, but there may be some
lingering cells around APF during the early evening hours.
&&
.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach 91 77 90 75 / 50 40 60 40
Fort Lauderdale 90 78 89 77 / 40 40 50 50
Miami 90 77 90 77 / 40 30 50 50
Naples 88 77 88 76 / 40 30 50 20
&&
.MFL Watches/Warnings/Advisories...
FL...None.
AM...None.
GM...None.
&&
$$
DISCUSSION...27/JT
MARINE...27/JT
AVIATION...17/AR
Area Forecast Discussion
National Weather Service Marquette MI
501 AM EDT SUN SEP 18 2016
.SHORT TERM...(Today and tonight)
Issued at 453 AM EDT SUN SEP 18 2016
Water vapor loop and latest RAP analysis shows a weakening shortwave
trough ne of Lake Superior moving slowly east through Ontario early
this morning. Focus for weather tonight into Monday shifts to a
complex of shortwave energy from the Pac NW to the Northern Rockies
which will approach the Upper Great Lakes in a zonal flow aloft over
the northern CONUS.
Today: Weakening shortwave ne of Lake Superior and assoc weak 700-
300 mb q-vector convergence could continue to support clouds and
isold shra over the far ern cwa this morning before shortwave
ridging and q-vector divergence/assoc subsidence spreads in from the
west in the afternoon. Otherwise look for generally clearing skies
and dry conditions across much of the area. Warm advection southwest
flow and mixing 85h temps of near 11C east to 14C west to sfc
should yield highs today in the low to mid 70s, warmest west half.
Tonight: Shortwave energy moving eastward along the Canadian border
will push a cold front across the Upper Lakes late tonight and early
Monday. While moisture will be somewhat limited and deeper moisture
will stay farther north, model consensus indicates there should be
sufficient forcing from shortwave and convergence along the front to
squeeze out isold to scattered showers mainly over the north half of
the area tonight closer to the better shortwave dynamics, better
isentropic ascent and deeper moisture with system. NAM model sounding
also show a few hundred j/kg of elevated CAPE across the northern
zones which will also warrant a mention of thunder. SPC has far wrn
cwa under a marginal risk for severe tonight, but given limited
instability and skinny elevated CAPE sounding profiles not expecting
any severe despite increase in deep layer shear. Expect lows generally
in the upper 50s to the lower 60s with the warmest readings along the
Great Lakes shorelines.
.LONG TERM...(Monday through Saturday)
Issued at 444 AM EDT SUN SEP 18 2016
Progressive pattern to begin the long term will give way to an
increasingly amplified pattern this week into next week. This will
occur as a ridge/positive height anomaly shifts into the Gulf of
Alaska/western Canada by mid week, forcing a deepening trof over the
western CONUS and ridging over much of the eastern CONUS. The
magnitude of the positive height anomaly at 500mb will increase to 3
standard deviations above the long term late Sept avg as it shifts
across the Northwest Territories to Nunavut late this week.
Underneath this strong positive height anomaly, the western CONUS
trof will only slowly progress eastward. Some recent GFS/ECMWF runs
show this trof deepening and closing off into a potentially large
mid level low over the Upper Mississippi Valley/Great Lakes region
early next week. If so, an unsettled, chilly period may be in the
offing just over a week from now. Until then, above normal temps
will prevail for the next few days before trending close to normal
mid and late week. As for pcpn, complex of shortwave energy racing e
along the U.S./Canada border region may result in some pcpn tonight
into Mon. After a dry day Tue, frequent rain chances will return Wed
thru Sun. However, if se Canada troffing is strong enough in
response to the western Canada ridge, baroclinic zone/frontal
boundary may be pushed far enough s to allow for a period of dry
weather later this week. That said, the overall look of the pattern
could support the potential of mdt to hvy rain at times as abundant
deep layer moisture will be avbl in the vcnty of a wavering sfc
frontal boundary setting up from the northern/central Plains to the
Great Lakes. As a result, although little pcpn will occur over the
next few days, pcpn amounts for this 7 day period should end up
above normal, potentially well above normal.
Beginning Mon, cold front and band of deep layer forcing associated
with shortwave energy reaching the area late tonight will shift e of
the area by Mon aftn. So, any isold/sct shra/tsra over the e half of
the fcst area in the morning should exit by aftn. As has been the
case over the last few days, some model guidance still show the
potential of a few -shra streaking across the area in the aftn in
association with trailing shortwave energy and a band of mid level
fgen. Given the relative dryness of the air mass following fropa,
pcpn seems unlikely with the exception of the far eastern fcst area
where boundary layer moisture will still be elevated into the aftn.
Included schc pops later in the aftn in that area. With skies
becoming mostly sunny, tight pres gradient/deep mixing will result
in breezy conditions developing, particularly over the w half where
most sunshine is expected. Winds will be strongest over the Keweenaw
with fcst soundings showing potential to mix to 40kt winds aloft,
raising the possibility that a wind advy may be needed. It will be a
warm day with fcst soundings suggesting max temps well into the
70s for much of the area.
With a deep dry air mass over the area, dry weather is expected Mon
night/Tue. Despite clear skies and pwat falling to 0.4-0.5 inches
Mon night, temps won`t fall as much as would be possible due to
relatively tight pres gradient with 925mb winds remaining mostly in
the 20-35kt range. Traditional interior colds spots over the w half
could slip toward 40F. Temps will range up well into the 50s to near
60F across the n where low-level wind fields will be strongest.
Winds will still be on the breezy side Tue with fcst area btwn sfc
high pres ridge to the s and sw and deep low pres over Hudson Bay.
Winds will again be strongest on the Keweenaw, but not as strong as
Mon. With sunny skies at least into early aftn, highs on Tue will
top out mostly in the lower to mid 70s with dwpts down into the 40s
away from lake moderation.
Trof that will be amplifying into the western CONUS Tue/Wed will
pick up energy off the southern CA coast and send it ne, reaching
the western Great Lakes Wed evening. With pwat surging up to 1.5
inches and assistance of upper divergence associated with right
entrance of upper jet across northern Ontario/Quebec, expect shra to
overspread the area Wed aftn/night.
A couple of days ago, medium range models began to indicate the
possibility of sufficient troffing developing over se Canada in
response to the western Canada ridge to allow sfc high pres ridging
to build se into the Upper Lakes Thu and potentially thru Fri. The
signal has not been consistent since then, but 00z medium range
models are in better good agreement on this scenario, which seems
reasonable based on the strength of the positive height anomaly
shifting into n central Canada. In addition, there appears to be
decent support from the Canadian and especially the GFS ensembles
for this evolution. If correct, baroclinic zone/frontal boundary may
shift far enough s to mostly end pcpn chc across the fcst area later
Thu into Fri. Since consistency on this idea has yet to solidify on
multiple model runs, fcst will still maintain some pops both days,
especially across the s.
Pcpn chances should increase over the upcoming weekend as the
western trof slowly approaches. However, significant spread develops
among the GFS and Canadian ensembles with some not even moving the
trof to the Great Lakes region. With the uncertainty, a simple model
consensus was utilized for the fcst Sat/Sun.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 137 AM EDT SUN SEP 18 2016
The main issue this TAF period will be the potential for MVFR
ceilings at CMX and IWD overnight. VFR conditions expected at SAW
through the period and will return Sun morning to CMX and IWD.
&&
.MARINE...(For the 4 AM Lake Superior forecast issuance)
Issued at 433 AM EDT SUN SEP 18 2016
Winds will remain generally below 20 kts today into this evening.
Tightening pres gradient between high pressure area over the Plains
and low pressure tracking through northern Manitoba toward Hudson
Bay will cause SW winds to increase as high as 25 knots late tonight
and to 30 knots on Monday as shift wsw in the wake of the cold front
associated with the Canadian low. In fact, there could be a period
of gale gusts to 35 knots between Isle Royale and the Keweenaw
Peninsula late Monday morning into the afternoon hours as west-
southwest winds will become enhanced by channeling between these
features. West winds should generally diminish to 25 knots Mon night
into Tue as gradient slackens with Canadian low lifting farther ne
across Hudson Bay. Winds will diminish to less than 20 kts
Wednesday into Friday under weak pres gradient across the Upper
Lakes.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Voss
LONG TERM...Rolfson
AVIATION...07
MARINE...Voss
Area Forecast Discussion
National Weather Service Paducah KY
324 AM CDT SUN SEP 18 2016
.SHORT TERM...(Today through Tuesday night)
Issued at 324 AM CDT Sun Sep 18 2016
Models show a weak upper level trof moving across the PAH forecast
area this afternoon. GFS keeps us dry, while ECMWF and HRRR generate
some light QPF mainly west of the Mississippi River this afternoon.
Included some slight chance pops for showers for a portion of our
southeast Missouri counties from 17z to 23z to account for it.
Despite northerly winds and some cloud cover, temperatures will be
a bit above seasonal normals today and tonight. Highs will be in
the lower to middle 80s with lows in the 60 to 65 degree range.
For tonight into Monday, surface high pressure will be sliding
east across our region. Winds will shift back to the south, and
temperatures will warm a few more degrees for Monday into Tuesday
night. Models show a weak cold front moving into the middle
Mississippi and lower Ohio River valleys Tuesday and washing out
Tuesday night. Models keep us dry, and the only result will be
light winds shifting to the north Tuesday night.
.LONG TERM...(Wednesday through Saturday)
Issued at 324 AM CDT Sun Sep 18 2016
Above average confidence through most of the period, then average
to below average at the very end due to slight model inconsistencies.
Still very little to discuss and very few changes synoptically
through most of the long term period. High pressure at the surface
and ridging aloft is forecast through most of the long term period
producing dry, warm, and humid conditions.
Friday night the GFS continues to weaken and suppress the upper
ridge slightly southward allowing a back door cold front to sag into
the far northern and northeastern sections of our CWA on Saturday.
In the process it also cranks out a few hundredths of QPF over the
same areas.
During the same time frame the ECMWF weakens the ridge but shows
deeper moisture and small precipitation chances over the southern
and western sections of our CWA on Saturday. The latest Superblend
model run appears to be picking up on that so will just go with
that which indicated slight chances area wide.
Temperatures will remain at or above normal through the period.
&&
.AVIATION...
Issued at 1157 PM CDT Sat Sep 17 2016
Fog has begun to form across much of the region late this evening,
mainly in the kevv/kowb areas. Given the already dense nature of the
fog at some sites in southern IL and western KY, it appears lifr
conditions will occur at kevv/kowb through the early morning hours.
Fog is expected to form at kpah/kcgi during the overnight hours, and
lifr conditions are likely at times. Improvement is expected once
the sun burns off the fog Sunday, however it may be a little slower
than earlier forecast. The fog should lift into a cloud deck around
mid-morning, likely mvfr through midday. It may be mid afternoon
before vfr conditions are prevalent.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
SHORT TERM...RST
LONG TERM...JP
AVIATION...MY
Area Forecast Discussion
National Weather Service Albany NY
1025 AM EDT SUN SEP 18 2016
.SYNOPSIS...
A cold front will slowly move towards the region from the eastern
Great Lakes and southeast Canada today with showers and some
thunderstorms. A disturbance will move along the front for an
extended period of rainfall tonight into Monday. The front moves
east and weakens Monday night into Tuesday...as drier air filters
in but temperatures will still be above normal.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 1025 AM EDT...An upper level disturbance and a prefrontal
sfc trough continue to focus a few bands of showers this morning
across the southern half of the forecast area. The latest HRRR
composite reflectivity shows a nice break in the pcpn which
should last through mid day. After this brief lull in the pcpn
...then along the southern periphery of the sfc trough some
isolated to scattered showers and thunderstorms may rekindle. The
latest HRRR is hinting at this possibility too. SBCAPE values are
generally in the 500-1000 J/kg range on both the NAM/GFS with some
slightly higher pockets possible in the mid- Hudson Valley and NW
CT. The deep shear is not especially strong with 25-30 kts with
mid level lapse rates in the 6-6.5 C/km range. The limited
instability and heating should keep any thunderstorms from being
severe...but if higher values of instability are realized...then a
rogue one or two could be possible with some strong winds.
Highs today will generally be in the 75-80F range in the valley
areas...and over the hilltowns...with upper 60s to lower 70s over
the mountains. Humidity levels will be on the sticky side with
dewpts rising into the 60s.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
Tonight...The cold front makes very slow progress eastward...and
a mid-level disturbance moves north-northeast from eastern TN and
Piedmont area. A plume of higher PWAT air will continue to be over
the region with values of 1.5-2.0" which are 1-3 standard
deviations above normal with the higher values from the Taconics
eastward into western New England. Showers with isolated to
scattered thunderstorms will evolve into a rainband or rainshield
ahead of the front. Periods of moderate to occasionally heavy rain
is possible overnight...especially from the Capital Region...and
eastern Catskills south and east. The highest POPS were included
here. Lows will be on the muggy side with mid and upper 60s from
the Tri Cities south and east...and upper 50s to lower 60s north
and west.
Monday...The mid and upper level flow from the S to SW to the N to
NE continues to be parallel to the sfc front which will continue
the threat of rain...especially in the morning. Some clearing over
the northwest portion of the forecast area is possible in the
afternoon. The above normal PWATS and better H850 theta-e
gradient continue to be over the southeastern portion of the ALY
forecast area. A gray and humid start to the week is likely with
period of showers and a chance of thunderstorms. The instability
looks even less on MON...especially from the GFS with SBCAPES of
250-500 J/kg. The antecedent conditions are dry leading up to this
multiple day event...but some ponding of water on roadways and
poor drainage flooding of low-laying areas may be possible Monday
morning into the afternoon. Highs will mainly be in the mid and
upper 70s with some cooler readings over the mountains /upper 60s
to lower 70s once again/.
Monday night...The front finally make some steady progress across
New England with isolated to scattered showers ending over the mid
Hudson Valley and NW CT early in the evening. The boundary may
actually fall apart with a weakening thermal gradient. Dewpts
fall in the 50s to lower 60s with some clearing skies. In the weak
cold advection regime lows fall back into the mid 50s to lower
60s.
Tue-Tue night...A secondary cold front...and the upper trough axis
approaches and dampens out during the day. Isolated showers are
possible north and west of the Capital Region. More sunshine will
allow temps to be at least 10 degrees above normal with the latest
GEFS having H850 temps 1 to 2 standard deviations above normal
with /+12C to +15C range/ with highs in the upper 70s to lower 80s
in the valleys...and lower to mid 70s over the higher terrain.
High pressure begins to ridge in from the Midwest and lower Great
Lakes Region with lows generally in the 50s with some upper 40s
over the southern Adirondacks.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Guidance is in good overall agreement with the longwave pattern.
Mid week have a fast zonal flow along the United States-Canadian
border on the southern periphery of an upper low over Hudson`s Bay.
As we head into the latter part of the week a large upper low
develops over the western United States with a sharp narrow ridge
forming between the lows.
For our area looking at mainly fair and dry weather. The only chances
for rainfall are expected with a backdoor front which should move
southward across the region early in the weekend. Temperatures are
expected to remain above normal by 5 to 10 degrees until the backdoor
front moves through ushering a more seasonable airmass in.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
Showers associated with a pre-frontal trough and approaching short
wave continue to move across the area and are expected to do so
through the early morning hours. MVFR will occur at times with the
showers with overall conditions expected to lower to MVFR this
morning. After these showers move off a bit of a lull is then
expected.
With the help of daytime and a humid airmass in place and the approach
of a stronger short wave storms are expected to develop with a focus
more to to the south and east of the Capital District. Overall chances
for the storms will increase as we head through the nighttime hours as
the approaching cold front move into the region.
A return to VFR conditions are expected by afternoon, however any storm
impacting a site will result in MVFR and possibly brief IFR conditions.
Conditions are expected to lower back down to MVFR with increasing chances
for showers tonight.
Southerly flow continues at less 10 knots.
Outlook...
Monday Night: No Operational Impact. NO SIG WX.
Tuesday: No Operational Impact. NO SIG WX.
Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: No Operational Impact. NO SIG WX.
Wednesday Night: No Operational Impact. NO SIG WX.
Thursday: No Operational Impact. NO SIG WX.
&&
.FIRE WEATHER...
A cold front will slowly move towards the region from
the eastern Great Lakes and southeast Canada today with showers and
some thunderstorms. A disturbance will move along the front for an
extended period of rainfall tonight into Monday.
Humidity levels will be high the next few days with 60 to 75
percent readings this afternoon and Monday afternoon...and 90 to
100 percent readings tonight.
A widespread wetting rain is likely the next 36 hours with 1 to
1.5 inches possible.
The winds will be southerly today at 10 to 15 mph...and then will
lighten to less than 10 mph tonight into Monday.
&&
.HYDROLOGY...
No widespread hydro problems are expected the next 5 days ending
on Thursday.
Some beneficial rainfall is expected over the hydro service area
/HSA/ today through Monday. A slow moving cold front and multiple
disturbances moving along or ahead of it will bring one to one and
half inches of rain to the HSA...with some locally higher amounts.
The higher totals will likely be south and east of the Capital
Region.
The system will tap into tropical moisture from the Gulf of
Mexico with precipitable water levels increasing to over 1.5
inches ahead of the cold front. Some isolated to scattered
thunderstorms are possible today and tomorrow. Some of the
downpours from the convection may yield ponding of water and poor
drainage flooding of low lying areas.
Drier weather returns by Tuesday...and may continue through the
mid week.
The U.S. Drought Monitor was released on September 15th and shows
drought conditions have worsened across portions of the Northeastern
United States as much of the region experienced above-normal
temperatures and below-normal precipitation. A (local) Drought
Information Statement was issued this past Friday evening
(ALBDGTALY).
For details on specific area rivers and lakes, including observed
and forecast river stages and lake elevations, please visit the
Advanced Hydrologic Prediction Service /AHPS/ graphs on our
website.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...SND/Wasula
NEAR TERM...11/Wasula
SHORT TERM...Wasula
LONG TERM...IAA
AVIATION...IAA
FIRE WEATHER...BGM/Wasula
HYDROLOGY...BGM/Wasula
Area Forecast Discussion
National Weather Service Bismarck ND
901 AM CDT Sun Sep 18 2016
.UPDATE...
Issued at 858 AM CDT Sun Sep 18 2016
Will spread the sprinkles to the east across the James river
valley through noon and also end sprinkles north cental as clouds
are clearing fast in good subsidence across the west. Otherwise
current forecast looks ok.
UPDATE Issued at 633 AM CDT Sun Sep 18 2016
Surface observations in western ND and eastern MT indicate there
is some precipitation reaching the ground. Highest reflectivities
are currently moving from the northwest into north central ND with
lighter reflectivities extending into the southwest. Added a
mention of sprinkles this morning for this quick moving activity.
HRRR shows reflectivities weakening as they move into central ND
so for now did not extend these all the way into the James River
Valley. Otherwise no significant changes to the going forecast. No
changes to the current wind advisory. Will send updated text
products shortly.
&&
.SHORT TERM...(Today and tonight)
Issued at 338 AM CDT Sun Sep 18 2016
The main forecast issue in the short term period will be wind and
fire weather concerns.
Currently, low pressure over southern Canada with a warm front over
eastern ND. Abundant mid and high level cloudiness is streaming
across western and central ND ahead of a strong 120+ KT Jet
screaming across the northern Rockies. Forcing associated with the
jet is producing some mid level returns over the northern tier
counties. Could see a few sprinkles this morning but at this time
will not introduce any pops. A little stronger wave riding on the
north side of the jet passes over this area this afternoon and could
produce an isolated thunderstorm. Not really impressed with the
chances but will maintain some small pops far north for consistency.
NAM/ECMWF do generate some light qpf near the international border.
Main concern today will be strong winds. NAM/GFS BUFKIT soundings
indicate advisory criteria winds just above the surface this
afternoon over western ND. Mostly cloudy skies this morning will
give way to afternoon sunshine and good mixing conditions. Winds are
also unidirectional through the mixed layer with a good 40+ knots at
the top of the mixed layer. With lapse rates increasing to nearly
adiabatic this afternoon, think there will be a period of 3-5 hours
of advisory criteria winds over the west. Winds are not as strong as
you move into central ND, so limited the advisory to west of the
Missouri River over the south central. Winds may be breezy this
evening, especially north, but they should drop below advisory
criteria by 00z. Will issue a wind advisory for western ND from 1 pm
through 7 pm CDT.
Did bump afternoon highs a few degrees above guidance again today.
Quiet tonight with lows in the mid 40s to lower 50s. Jet induced
clouds skirt the SD border with perhaps a stray sprinkle or shower
trying to sneak into ND but will not mention any precipitation at
this time.
.LONG TERM...(Monday through Saturday)
Issued at 338 AM CDT Sun Sep 18 2016
Quiet early in the extended period but increasing shower chances as
we move into the latter half of the work week.
Although there are significant differences, the deterministic models
have come into better agreement with the evolution of a closed upper
low that develops over the Pacific Northwest on Tuesday and drops
south into the inter-mountain west through Thursday and eventually
lifts into the northern plains by Friday into Saturday.
The leading shortwave energy moving through the developing low first
reaches the northern plains Tuesday night into Wednesday bringing a
chance of showers. We then see a dry spell Thursday into Friday as
upper level ridging builds over the area, ahead of the digging upper
low to our west. At this time...think the models may be too
aggressive bringing pops into the area Wednesday night through
Thursday, especially over central ND. At this time, will pass
this along to the next shift and will stick with guidance pops,
given we are still quite a ways out and models are just beginning
to converge. If the trend continues think we may see a paring down
of pops Wednesday night into Thursday.
As the upper low approaches late in the work week and over the
weekend it looks like a potentially wet Friday ahead of the storm
system, then possibly a break for at least some of us on Saturday as
we get dry slotted with the los lifting into far eastern Montana.
Finally just beyond the extended period, showers move back over the
area on Sunday as the storm system tracks across the northern
plains.
Right now it looks like mainly rain showers with this system.
Although a period of thunder can`t be ruled out with such a dynamic
system, most of the instability remains to our south. It also looks
like all liquid precipitation at this time. Although this is a
strong system and we are certainly getting into the time of year
where you can see some snow on the back side of these lows. This
will certainly be a system to watch as we go through the upcoming
week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 633 AM CDT Sun Sep 18 2016
Main aviation highlight will be gusty westerly winds increasing
behind a cold frontal passage today. Expect westerly sustained winds
to 25kt with gusts 35kt-40kt at KISN/KDIK/KMOT. Sct/Bkn cigs at or
above 9000ft agl can be expected through the morning, with
decreasing clouds during the afternoon. Few/Skc after 00z Monday.
&&
.FIRE WEATHER...
Issued at 338 AM CDT Sun Sep 18 2016
We have lowered minimum humdities lower than current guidance.
This puts us within reach of fire weather highlights, given the
strong winds and forecast minimum humidities. However, at this time,
grasses have yet to cure fully, except possibly in the far southwest
part of the state. We are expecting an increasing westerly wind
today, not an abrupt shift. Thus although marginally sufficient
for a Red Flag Warning, we will hold off due to the limited area
of dry fuels and the lack of an abrupt wind shift. Should
humidities drop even lower than forecast, the day shift may need
to re-visit.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from 1 PM CDT /noon MDT/ this afternoon to 7 PM
CDT /6 PM MDT/ this evening for NDZ001>003-009>011-017>021-
031>034-040>045.
&&
$$
UPDATE...WAA
SHORT TERM...TWH
LONG TERM...TWH
AVIATION...KS
FIRE WEATHER...TWH
Area Forecast Discussion
National Weather Service Columbia SC
634 AM EDT SUN SEP 18 2016
.SYNOPSIS...
Julia will continue to meander off the South Carolina for the next
few days. High pressure ridging into the area from the north will
weaken today. An approaching cold front will move into the area
Monday. The development of a weak upper level low will keep the
chance for convection across the area through much of week.
&&
.NEAR TERM /THROUGH TONIGHT/...
Upper level ridging and surface high pressure will weaken across
the area today. An upper level trough crossing the Mississippi
River Valley will continue moving east into the Ohio River Valley
and Tennessee Valley tonight.
Upper level difluent flow across the area combined with weak
instability this afternoon could aid the development of isolated
convection eastern Midlands. The chance for convection will also
increase across the western Midlands and CSRA late in the day as a
cold front approaches from the west and weak short wave energy
moves into the region. We went with slight chance pops cross the
eastern and western Midlands as well as the CSRA...and dry
conditions over the central Midlands today. The chance for showers
and isolated thunderstorms will increase overnight as a weak cold
front approaches from the west. Ahead of the front the airmass
will remain weakly unstable with precipitable water increasing to
around 2.00 inches.
Went with persistence for afternoon highs around 90 degrees and
lows tonight around 70.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
An upper level trough and its associated weak cold front will
cross the area Monday. Models are now indicating a cut off low
developing over the eastern Carolinas late Monday. We could also
see some interaction with Julia. Have indicated the highest pops
on Monday with at least a slight chance for convection lingering
though Wednesday.
Kept temperates near census for highs in the mid 80s to around 90
degrees and lows in the upper 60s and lower 70s.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
Both the GFS and ECMWF show the weak upper low remaining over the
region into Saturday. This features combined with a moist onshore
flow and weak instability has warranted a chance of mainly
diurnal convection each day. Daytime highs are expected to be in
the mid to upper 80s with lows in the upper 60s and lower 70s.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
Lower confidence forecast this morning for all sites.
Models still indicating the possibility of broken stratus and/or
br development this morning. HRRR would currently indicate that
the region should be covered in low-stratus. Other guidance also
indicating low-clouds. However, satellite and surface obs only
indicting a few areas of mid and high level clouds, and a some
sites with visibilities around 6sm in br. Confidence in models not
that high this morning. Can not rule out some stratus developing
after sunrise in some areas for an hour or two, but based on
current cloud heights would tend to see ceilings at or above 3kft.
Forecasting mainly vfr conditions at this point, with above stated
lower confidence. For this afternoon, isolated showers/storms may
develop late in the afternoon, but not enough confidence to
mention at any of the TAF sites at this time. Winds generally
light and variable through the period.
EXTENDED AVIATION OUTLOOK...Early morning fog and stratus remain a
possibility through the period with a chance of mainly
afternoon/evening thunderstorms early next week.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
&&
$$
Area Forecast Discussion
National Weather Service Caribou ME
936 AM EDT SUN SEP 18 2016
.SYNOPSIS...
A warm front will cross the region today. A weak frontal system
will track through the region Monday. A strong cold front will
move through later Tuesday, bringing cooler and drier weather
Wednesday and Thursday.
&&
.NEAR TERM /THROUGH TONIGHT/...
Update...
Latest radar reflectivity imagery shows whats left of the shower
activity associated with the departing short wave is quickly
crossing the international border. Latest HRRR data is showing
little in the way of precipitation is expected this afternoon
although a stray shower couldn`t be ruled out. Could even see a
few glimpses of the sun across northwest Maine by early afternoon
per latest visible satellite imagery showing a bit of a break in
the clouds along the St.Lawrence seaway. The main changes to the
going forecast was to lower the probability of precipitation for
this afternoon otherwise forecast is in good shape.
Previous Discussion...
A warm front and upper level disturbance will move east of the
region early today. Rain this morning will taper to scattered
showers this afternoon. Patchy fog is also possible this morning.
Expect partly/mostly cloudy skies across northern areas this
afternoon, with mostly cloudy skies Downeast. Another upper level
disturbance will approach from the southwest later tonight. Skies
will remain mostly cloudy Downeast tonight with increasing shower
chances overnight. Cloud cover will increase across northern areas
overnight along with scattered showers. Patchy fog is also
possible across the entire region later tonight. High temperatures
today will range from the lower to mid 70s across the forecast
area. Low temperatures tonight will range from the upper 50s to
around 60 north, to around 60 to the lower 60s Downeast.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
A trough will persist over the region Monday in a moist
southwesterly flow. This will result in showers through the day
and into the evening. The trough will move to the east Monday
Night with showers confined to the southeastern portion of the
region. A cold front is then expected to approach from the
northwest Tuesday. This is expected to bring showers to northern
areas during the day Tuesday while the south remains partly
cloudy.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Strong high pressure is expected to approach from the west
Wednesday and crest over the state Thursday with dry conditions
expected on both days. Low pressure approaching from the west is
expected to bring showers to the area Thursday Night into Friday.
Strong high pressure will build down from the northwest Saturday.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: MVFR to LIFR conditions are expected across the entire
region this morning. Conditions should improve to VFR levels
across northern areas this afternoon, with generally MVFR
conditions Downeast. VFR conditions are expected across northern
areas early tonight, then lowering to MVFR/IFR levels overnight.
MVFR/IFR conditions are expected early tonight Downeast, with
IFR/LIFR conditions overnight.
SHORT TERM: Expect IFR conditions Monday and in the north
Tuesday. MVFR conditions are expected in the south Tuesday. VFR
conditions are expected Wednesday and Thursday.
&&
.MARINE...
NEAR TERM: Marginal small craft advisory conditions are expected
across much of the waters today. A Small Craft Advisory remains
in effect for much of the waters, with the exception of the
intracoastal waters, through this afternoon. Conditions are
expected to be below small craft advisory levels tonight.
Visibilities will be reduced in patchy fog today through tonight.
Rain this morning will taper to scattered showers this afternoon.
Shower chances will then increase again tonight.
SHORT TERM: Have used the GFS20 to populate the sustained wind
grids. For waves: For Monday and Tuesday expect southwesterly wind
wave (2 feet/5-6 seconds) to be the primary wave system with a
secondary southeasterly long period wave group 1 foot/8-9
seconds).
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ050-
051.
&&
$$
Near Term...Duda/Norcross
Short Term...Mignone
Long Term...Mignone
Aviation...Duda/Norcross/Mignone
Marine...Duda/Norcross/Mignone
Area Forecast Discussion
National Weather Service State College PA
1126 AM EDT SUN SEP 18 2016
.SYNOPSIS...
A plume of deep moisture streaming north into Pennsylvania all the
way from the Gulf Coast region will interact with a slow moving cold
front and a few disturbances aloft to bring occasional showers and
thunderstorms through the rest of the weekend.
Rainfall totals by Monday will likely be near one inch in many
locations. Improving conditions with decreasing humidity will
occur Monday and Tuesday as high pressure builds in from the
midwest. Temperatures will again rise to well above normal levels
again later in the week.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
Relatively warm moist mid-September morning. Satellite shows a
cloud band in eastern Pennsylvania and a deeper cloud band with an
associated surge of high PW air to the south and west. There are
some areas with breaks in the clouds with some sunshine.
The deep moisture plume with the cloud band over west-central PA
will dominate our weather over the next 0-24 hours. WV shows this
plume of moisture is quite deep over WV/KY/TN. Not surprisingly the
GEFS/GFS/HRRR all show a surge of high PW air into the region
today into tonight.
The convective allowing HRRR and GFS/GEFS have some similarities.
GFS/GEFS show convective-like areas of QPF by 18Z and rapidly
increasing POPS over central PA by 21Z today. So by 2 PM expect
increasing chance of showers and thunderstorms and wider showers
and thunderstorms by early evening. It takes until about 10 PM for
the GEFS to show good probabilities of 0.25 inches of QPF, over
central Pennsylvania. Less to west and east. Not a gang buster
event for most locations.
The Convective Allowing Model (CAM) suggests convection breaks out
first in the west/southwest around 16-18Z. A fast moving wave
brings rain across central counties to the NY border in the 2 PM
to 6 PM range with a good lull behind it. Lighter rain breaks out
behind it to the south and to the northwest. The coverage looks
considerably lower than the GFS/GEFS. Most areas in the HRRR get
1-3 hours at best of rain time. The convective nature of the HRRR
is such that the cores could produce 0.25 to 0.75 inches of
rainfall in areas affected by the convective cores. The HRRR like
the GFS/GEFS is wetter in central PA but the HRRR extends this
farther east. From near State College to Williamsport to
Bloomsburg and Berwick. The will change with every run.
So expect possible showers and thunderstorms this afternoon/eve.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH MONDAY NIGHT/...
The CAM does not go too deep into this period but shows some rain
through midnight. The GEFS implies 5 PM Sunday through about 4 AM
Monday is the best time for most of central PA to have at least
0.10 inches of rain. It is also the peak window for a 0.50 inches
of rain mainly in central PA with areas of 0.75 to 1.00 inches of
total QPF. The GEFS has a wet bias so 0.50 to 0.70 is more likely.
But the GEFS implies at least a 50 percent chance of 1 inch or
more QPF mainly in central PA. Less in south/southeast and
north/northwest.
The GEFS implies rapid west to east drying out Monday morning.
There is no QPF over the western third of our region on/after 7
AM. Slower to get out of the southeast. The GEFS keeps the
lingering chance to 5 PM Monday. The GEFS is too slow to diminish
QPF and we suspect the afternoon will likely be nicer in southeast
PA than current model QPFs imply. The flow is weak and getting
rid of the clouds might be problematic.
POPS should be inconsequential Monday afternoon and near 0
overnight Monday into Tuesday AM. Good night for low cloud and fog
formation. The low-level flow is extremely weak implying very
light winds.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
High pressure will bring some dry weather for Monday night and
Tuesday.
The next cold front in the pattern is destined to run into rising
heights aloft over the northeastern US Tuesday. The normally wet
GFS shows the band of showers associated with this system drying
up as it moves through the eastern Gr Lakes. The ECMWF also shows
the showers dying, but not totally as they move into the region by
late Tuesday. I used the SREF/GEFS pops which lead to a higher
confidence that the GFS will be correct keeping us dry.
The midweek through weekend timeframe will feature a rebound in
the amazingly persistent (this summer) eastern US/western
Atlantic upper ridge. The NAEFS shows anomalously high upper
heights and warm temps from Wed into the weekend. So the upcoming
week promises to be yet another warmer than normal one and
basically dry as no significant chance for rain seems to be in the
cards.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
A plume of deep moisture will provide for mostly cloudy to
overcast skies today. Showers should spread southwest to northeast
across the State. Some embedded thunderstorms are possible. Thus
there will be areas of MVFR today in western areas with the
clouds. As the rain moves to the north and east most locations
will see a few hours of rain and MVFR and IFR conditions will
possible.
The rain peaks in eastern areas this evening and overnight. Light
winds and high moisture will produce areas of fog and low clouds
to add to the flight restrictions. Widespread areas of IFR and
some LIFR are possible overnight Sunday into Monday.
The drier air should begin to improve conditions in northwestern
PA early Monday. Farther east, behind the frontal boundary on
Monday it will clear west to east. Thus mainly VFR conditions are
expected for the balance of the week, except for chances of
morning fog and low clouds.
Outlook...
Mon-Thur...AM valley fog possible, otherwise, no significant
weather.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Lambert
NEAR TERM...Grumm
SHORT TERM...Grumm
LONG TERM...La Corte/Lambert
AVIATION...Grumm/Jung
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
624 AM CDT Sun Sep 18 2016
.Discussion...
Issued at 339 AM CDT SUN SEP 18 2016
Water vapor showing a compact upper shortwave trough moving through
central Kansas this morning with radar trends depicting isolated
convection associated with this feature well to our west. Prevailing
thought out of the gate is that much of this activity will dissipate
with further eastward progress this morning...however a light
sprinkle cannot be ruled out for northeast Kansas and far northwest
Missouri per the latest HRRR runs. Despite this...activity looks
pretty anemic on TWX radar and will hold off on any precip mention
unless trends in the next few hours suggest otherwise. Aside from
some early morning cloud cover...today is shaping up to be a
beautiful late September day with well above normal temperatures as
highs climb into the lower to middle 80s. 850 temps this afternoon
will be a few degrees warmer than yesterday by 00z as southerly flow
returns following the passage of a weak warm front this afternoon.
This will mark the beginnings of a fairly decent warming trend as
highs on Monday flirt with the 90s degree mark out ahead of a weak
cold front that will be sagging south through Iowa throughout the
day. In terms of sensible weather impacts...latest model runs have
backed off on precip chances for the lower Missouri Vly Monday
afternoon as convergence into the aforementioned front remains weak
at best. The next chance for organized shwr/storm activity looks to
hold off until Tuesday night/early Wednesday models suggest an MCS
may clip northern portions of the fcst area during the early morning
hours...although its likely many areas will remain dry with lack of
any substantial midlevel forcing. Otherwise the remainder of the
work week looks dry with above average temperatures continuing. Big
changes finally look to be in store for the weekend as a strong
longwave trough and associated cold front move through the region
Saturday night/early Sunday. This should result in renewed precip
chances and cooler temps late in the forecast period.
&&
.Aviation...(For the 12Z TAFS through 12Z Monday Morning)
Issued at 624 AM CDT SUN SEP 18 2016
VFR conditions expected through the forecast period with light winds
from the south between 5-10 kts. SCT-BKN 100-120 kft layer will
gradually dissipate by late morning as upper disturbance exits the
region. This may be followed by some fair wx CU development this
afternoon with bases centered between 6-8 kft. No major hazards
expected.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...None.
MO...None.
&&
$$
Discussion...32
Aviation...32
Area Forecast Discussion...UPDATED
National Weather Service Fort Worth TX
1015 AM CDT SUN SEP 18 2016
.UPDATE...
The main update for this morning was to adjust PoP and Wx grids
based on radar and satellite trends. Other than a few cosmetic
changes to the temperatures, the rest of the forecast looks to be
in good shape.
The morning thunderstorm complex that strolled across the
northern third of North TX continues to slide off to the east. As
subsidence overspreads much of North and Central TX, it`s unlikely
that additional convective development will take place later
today. The exception to this will be for areas along and south of
a Killeen to Athens line where a southward moving outflow boundary
may prove sufficient to produce some isolated to scattered
convection this afternoon. With surface winds continuing to veer
ahead of the outflow boundary, however, it`s likely that the
coverage of storms will be low and a 20-30% PoP should suffice for
southern/southeastern zones.
Otherwise, I`ve made a few minor adjustments to sky and
temperature grids based on current trends. Updated products have
been transmitted.
24-Bain
&&
.AVIATION...
/ISSUED 702 AM CDT SUN SEP 18 2016/
The primary aviation weather concern will be thunderstorms and
strong/gusty northwest winds associated with an eastward moving
storm complex. All storms should move east of the Metroplex TAF
sites by 14Z, then clouds will decrease from west to east. The
outflow may briefly make it to WACO between 13 and 14Z but it
will lose its punch so the wind shift will be subtle and brief.
All precipitation will move well east of the Metroplex TAF sites
before midday but Waco could see a few showers develop through
early afternoon.
This afternoon and tonight should be quiet across North and
Central Texas with VFR conditions and a south wind generally less
than 12 knots.
79
&&
.PREV DISCUSSION... /ISSUED 334 AM CDT SUN SEP 18 2016/
Two distinct areas of convection are ongoing across the state of
Texas early this morning. The first is a rapidly decaying area of
showers and a few lingering storms near San Angelo which are part
of a storm complex that developed this evening. The only impacts
from these convective remnants on our CWA will be a dense canopy
of mid and high-level clouds which should continue to thin through
the morning hours.
The second and more robust area of storms is a southeastward-
surging MCS which currently stretches from near Childress,
northeastward towards Oklahoma City. Latest RAP-based objective
analysis from the SPC reveals this complex presently exists within
a local minimum in instability, a result of earlier convection
across central and southern Oklahoma. Recent radar trends suggest
that the southern end of the MCS is beginning to build southward--
right down the backward/upwind propagating Corfidi Vector--along
a west-to-east oriented 925-850 mb theta-e gradient situated near
the Red River. As this complex and its associated outflow continue
to move southward into a somewhat more favorable thermodynamic
environment, it`s possible we see renewed convective development
into roughly the northeastern third of our CWA. Recent time-lagged
runs of the HRRR seem to be (within about an hour or two)
capturing the evolution of this MCS fairly well. Aside from some
temporal adjustments to speed up this system`s progression, I`m
hard pressed to find reasons to ignore its consistent forecast
signal.
Based on a combination of radar trends and high-resolution
guidance, expect strong gusty outflow winds to arrive across our
northwestern Counties (Young, Jack, Montague) shortly, around 4
AM, into the Metroplex around 6 AM, and then exiting our eastern
zones in the 9-11 AM time frame. While I can`t rule out the
potential for a marginal severe gust mainly our northern row of
counties, in general, anticipate gusts into the 40-50 mph range
across the northwestern counties, with a gradual decrease in gust
intensity as the outflow and storms press southeastward. Expect
showers and storms to follow behind the outflow boundary, building
southward towards the Metroplex and potentially even a few rows of
counties to the south and east later this morning.
Once this batch of convection clears the region during the mid to
late morning hours, things should quiet down with just a few
lingering showers. For this afternoon, convective coverage should
be minimal as our atmosphere will have become significantly
overturned--at least across the northwestern 2/3rds of the CWA.
Opted to leave in a low 20% PoP even in the northwest today as
earlier guidance suggested the atmosphere might recover enough to
support some isolated activity. Based on trends later this
morning, the day shift may be able to remove PoPs across a portion
of our western and northwestern CWA.
A dry stretch of weather is then in store for this coming week as
high pressure builds in overhead. High temperatures tomorrow will
get a noticeable boost into the mid and upper 90s. As we don`t
really scour out the lower-level moisture, heat index values
Monday will likely rise into the 100-104 degree range for many of
us during peak heating. Dewpoints will fall steadily, however, as
we get into the middle of next week. The next real shot of
precipitation looks to occur next Saturday as moisture returns
from the south.
Carlaw
&&
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 92 76 97 76 96 / 30 5 5 5 5
Waco 94 75 97 73 96 / 20 5 10 5 5
Paris 89 72 95 71 94 / 100 5 5 5 5
Denton 90 73 96 73 95 / 30 5 5 5 5
McKinney 91 73 96 72 95 / 60 5 5 5 5
Dallas 92 77 98 77 97 / 40 5 5 5 5
Terrell 91 74 96 74 95 / 60 5 5 5 5
Corsicana 92 75 96 75 95 / 40 5 10 5 5
Temple 93 74 96 73 95 / 20 5 10 5 5
Mineral Wells 92 72 97 71 95 / 20 5 5 5 5
&&
.FWD Watches/Warnings/Advisories...
None.
&&
$$
26/24
Area Forecast Discussion
National Weather Service Grand Rapids MI
1129 AM EDT SUN SEP 18 2016
LATEST UPDATE...
Hydro
.SYNOPSIS...
Issued at 329 AM EDT Sun Sep 18 2016
A high pressure ridge will cross Michigan today bringing
mostly sunny skies and highs in the 70s. A weak warm front will
cross the area tonight but have little impact on our actually
weather. A cold front will then push southeast into our area later
Monday bringing the threat of a few thunderstorms late in the day
or during the evening. Most locations around the area should stay
dry and not see these storms. Temperatures overall will remain
above normal through most of this coming week.
&&
.SHORT TERM...(Today through Tuesday)
Issued at 329 AM EDT Sun Sep 18 2016
The short term looks rather uneventful for the most part. There is
a remote chance of thunderstorm today then a slightly higher risk
for thunderstorms Monday afternoon into Monday evening.
The passage of an upper level trough through the area today may
result in an isolated thunderstorm (as shown by the HRRR and RAP
models for several runs in a row) but my thing is the air is so
dry at mid levels it is hard to imagine any storm really being
able to develop.
Tonight a warm front pushes through the area but the dynamics for
that are all north of our area and once again the mid level
moisture is lacking. Also the instability is lacking...there is a
slight amount of cape in the 700 to 600 mb range late tonight...
but given the amount of dry air it would be hard to form anything.
On Monday we have a cold front heading this way but the core of a
125 to 135 knot polar jet core is forecast to move largely east
along the Canadian boarder Monday into Tuesday. That puts
southwest Michigan in the right exit region of the jet...which is
hugely not favorable for convection (which is why mid levels are
so dry Monday into Monday night). Also due to this strong jet the
low level jet core max is well north of this area putting
southwest Michigan in a speed divergence area of the low level
jet...also a good event killer. There is elevated cape Monday
evening but with the dry air and other thing not being all that
favorable I remain unimpressed. Even so the latest SPC outlook
does show a marginal risk... I agree it is marginal. The SPC SREF
from 21z shows only a 5 pct chance of even seeing a thunderstorms
west of US-131 between 4 pm and 10 pm.
Beyond that...once the cold front is through we are in dry air so
jet educed subsidence so skies should be clear to mostly clear
Tuesday.
.LONG TERM...(Tuesday night through Saturday)
Issued at 329 AM EDT Sun Sep 18 2016
A fairly mild long term period is expected with highs 75-80. Zonal
flow aloft will push low pressure over the Plains east toward
Wisconsin by Wednesday night. The cold front associated with this
low will become oriented northeast to southwest from northern Lower
to near Kansas City. That`ll allow moisture to begin to pool along
it. As the front begins to move across the cwa Thursday,
precipitable water values increase to 1.75 inches. A few
showers/storms seems like a good bet with the best chance over the
northwest cwa and a couple of those could produce heavy rainfall.
The gfs and ecmwf differ a bit with the front in that the gfs pushes
the front through the cwa, but the ecmwf stalls it out and then
pushes it back north Friday night. Given the overall flatness of
the upper pattern, the ecmwf seems like a better solution. Thus
we/ll keep low chc pops in the forecast through Saturday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 722 AM EDT Sun Sep 18 2016
Over all I expect VFR conditons to prevail at all taf sites today
and tonight. There is some patchy fog this morning but it should
very quickly mix out. Tonight there should be enough wind in the
boundary layer to prevent fog from becoming much of a problem.
There is an upper level trough coming through the area today and
the HRRR and RAP models, run after run keep showing showers
developing around 12z then spreading inland by 16z as they move
out of the area. It seems to me the air is just to dry at mid
levels for showers to form so I did not put this in the TAFS but
it may be something to watch for in the next few hours.
&&
.MARINE...
Issued at 1056 AM EDT Sun Sep 18 2016
Will go ahead and issue a small craft advisory now starting around
daybreak Monday. Southwest winds will increase late tonight ahead
of an approaching cold front. Waves will build to 3 to 5 feet by
daybreak north of Holland, and to that level south of Holland
toward mid day Monday.
Note this issuance will not be accompanied by a beach hazard
statement since the season for that is ending later this Sunday
evening.
&&
.HYDROLOGY...
Issued at 1129 AM EDT Sun Sep 18 2016
The river advisory continues on the Sycamore Creek at Holt this
morning. River obs are reflecting that rises are beginning to
slow, which signals that the site is nearing its peak. The river
should top out around sunset and will begin falling late this
evening. Dry conditions will allow the river to continue to fall
through Monday.
A frontal boundary will bring additional rainfall Monday night.
Overall amounts are expected to be light (around 0.25" or less),
but brief bouts of locally heavy rain cannot be ruled out.
Flooding concerns are low at this time with a side note: Due to
near/above normal river levels, basins affected by any heavy rain
could see quick response times, mainly consisting of within bank
rises.
&&
.GRR Watches/Warnings/Advisories...
MI...None.
LM...Small Craft Advisory from 7 AM to 11 PM EDT Monday for
LMZ846>849.
Small Craft Advisory from 11 AM to 11 PM EDT Monday for LMZ844-
845.
&&
$$
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...99
AVIATION...WDM
HYDROLOGY...JAM
MARINE...JK
Area Forecast Discussion
National Weather Service Wilmington NC
1040 AM EDT Sun Sep 18 2016
.SYNOPSIS...
Tropical Depression Julia will continue to drift toward the
Carolina coasts, and may linger offshore into the upcoming
week. High pressure is expected to build into the Carolinas
Thursday and Friday.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 1030 AM Sunday...12Z RAOBs from MHX and even moreso CHS show
very dry air above 9000ft. As such these showers that are trying to
spiral shore will be hard-pressed to make it very far inland though
most guidance including recent runs of the HRRR seem to think so.
Latest radar trends not really supportive of precip very far inland
and if this trend continues will trim inland POPs-but will hold off
at this time in deference to the model consistency.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 300 AM Sunday...Chief weather headline this period is
Julia`s circulation will visit the area Monday just off Cape Fear.
This should fling occasional showers onshore favored north of Cape
Fear and churn up the surf a bit. Winds associated with Julia
should sustain around 20 kt according to forecast pressures, but
higher gusts will accompany the showers. The models have not done
historically well with Julia and this trend could still continue
so stay tune. For now will advertise scattered showers, isolated
TSTMS with highest POP values Monday afternoon and evening, and
best overall odds and highest qpf generally north of Cape Fear.
Late on Tuesday the gradient increases and onshore flow could
produce gusty coastal winds and rough surf north of Cape Fear as
well. Temperature maximums will run close to normal this period
with minimums slightly above normal due elevated vapor content and
onshore flow.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 330 AM Sunday...For Wednesday thru Friday, models show a
mid-level low closing off early Wednesday just north of the ILM
CWA and dropping to and meandering across the Southeast U.S.
Coast thru the end of this work-week. By the end of the week, it
is well south of the main belt of westerlies aloft. This weakness,
lingers across the mentioned region, possibly into the upcoming
weekend. The one question to ask, is if Julia, or the remnants of,
remain in the neighborhood, what will the interaction be when this
upper feature pushes to and across the FA. Julia has basically
defied the majority of the models with regard to basically her
existence up thru today, Sunday. At this point, models indicate
hier moisture across the fa during this 3 day period but is
limited in areal coverage. If temps aloft with this closed, and
eventually cutoff low, drop enough, then diurnally driven
convection over land areas will atleast require low chance and not
just isolated coverage. More cloudiness and POPs are advertised
for the ILM CWA thruout the extended, and thus have lowered the
daily maxes by a degree or 2 each day...and have upped the daily
lows by a degree or 2 also for each day since an onshore wind will
continue thruout this period. in essence, the diurnal range in
max/min temps will decrease compared to the previous updates.
Still though, we will remain at or a category hier than climo
norms.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
As of 12Z...A mixture of VFR/MVFR/IFR this morning will improve
to VFR within the next few hours as fog dissipates and low cigs
disperse. Isolated showers will move across the area today, with
conditions expected to deteriorate again late overnight into the
early morning hours on Monday, due to areas of fog and low cigs.
Patchy areas of fog and low cigs are creating MVFR/IFR this
morning, with northeast winds around 5 to 8 kts. Expect
conditions to improve to VFR within the next few hours, and
continue through the rest of today with isolated showers
possible. Winds will increase to around 10 kts and become
easterly this afternoon . Latest guidance continues to suggest
the potential for areas of fog and low cigs late overnight into
the morning hours on Monday, which may create MVFR/IFR.
EXTENDED OUTLOOK...Low chance for convection Monday thru Tuesday
due to a slow eastward moving frontal boundary oriented NE to SW
across the central Carolinas, and Julia, or the remnants of,
meandering near the coasts of both Carolinas. By Wednesday, this
front should push off the Carolina coasts with drier conditions
following for Thursday. Brief IFR conditions possible during the
pre-dawn hours each day from either low stratus or reduced vsby
from fog, possibly dense near sunrise each day.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/... As of 1030 AM Sunday...No changes to
the forecast. Previous discussion follows:
As of 630 AM Sunday...Seas to remain slightly elevated due to
wave energy from the winds of Julia but no advisory expected today
or tonight but a caution statement early. ESE-SE waves of 4-5 feet
every 7-8 seconds can be expected today with a slow subsiding
trend tonight into Monday, with similar wave-direction and wave
period. Isolated showers and TSTMS will move landward this period.
E-SE winds today and tonight mainly in a 10-15 knot range may see
gusts to 25 kt in showers and up to 20 knot inshore in the mid and
late afternoon with sea breeze enhancement. An isolated waterspout
offshore today or tonight should not be a complete shocker.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 300 AM Sunday...A cautionary statement at a minimum may be
needed for this period as the circulation of Julia approaches and
impacts the coastal waters. ESE-SE waves of 4-5 feet every 7-8
seconds will be locally agitated in bands of showers Monday. An
advisory is not out of the question for frequent gusts to 25 KT,
and again late Tuesday as high pressure building from the north
tightens the local pressure gradient against the remnant Julia
low still offshore. This period will need to be monitored as wind
and weather conditions may change relatively quick with a few
stronger gusts possible through the period.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
As of 345 AM Sunday...Nothing is written in stone for this
extended forecast. With confidence remaining on the low side with
respect to what and if Julia remain in existence come this time
frame. What sfc interaction will result if she does come in
contact with the weak dynamics associated with the mid-level
closed low that eventually becomes a cutoff low. The sfc pressure
pattern continues to display an onshore ne-e flow this period. The
sfc pg tightens somewhat and should yield 10-15 kt or a solid 15
kt windspeed. Will indicate significant seas in the 3 to 4 foot
range. It will be dominated by 8 to 9 second period e to ese
ground swell. Projected Karl Swell if he still is in existence,
will reach the ILM Coastal waters Wed night or early Thu as a
10-12 second period swell.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.
&&
$$
SYNOPSIS...DCH
NEAR TERM...MBB/MJC
SHORT TERM...MJC
LONG TERM...DCH
AVIATION...SGL
Area Forecast Discussion
National Weather Service Jackson MS
1038 AM CDT SUN SEP 18 2016
.UPDATE...Morning UA analysis showing much drier air over the
forecast area compared to 24 hours ago. PWATs are down from 2.26
inches yesterday to 1.66 today. Despite the overall dryness, low
level moisture remains quite high as evidenced by the veil of stratus
overspreading the area this morning. While mixing will be slow to
initiate, cloud deck should eventually rise and break up by
afternoon.
Satellite and radar data this morning is showing and MCS moving
through AR. The HRRR seems to be handling this feature well at the
moment on placement and intensity. Because of this, its solution of
the MCS eventually weakening and breaking apart as it moves into the
forecast area this afternoon seems reasonable, especially
considering the overall drier airmass it is moving into. IR data
seems to be confirming this with the warming cloud top trend of
late. Still, convergence along it outflow moving into the Delta
should be sufficient for scattered showers and a few thunderstorms.
Where storms can get going, some gusty winds do look possible. While
thermodynamic microburst checklist did not come up with much
potential this morning, existing 35 knots of deep layer shear may
enhance some downbursts./26/
&&
.AVIATION...Low stratus was plaguing most TAF sites across the region
once again this morning, resulting in a mix of MVFR/IFR flight
categories. The only exception to this was at KGLH where VFR
categories were being observed. Where these degraded categories are
currently being observed, ceilings will improve from MVFR to VFR
categories by early afternoon. Convection across the area today could
also lead to a brief degradation of visibilities to MVFR/IFR status
if observed on site. Winds today will begin from the south southwest
around 5 knots. However, as the afternoon and evening progresses,
winds will become more northwesterly./17/19/
&&
.PREV DISCUSSION... /issued 321 AM CDT SUN SEP 18 2016/
SHORT TERM...Today through Monday night...A small burst of
convection is currently being observed on radar this morning over
South Central Arkansas. This activity is associated with a
weakening disturbance shifting east near a weak cold front that`s
currently hung up to my north. If it holds together, it`ll bring
some shower activity and perhaps a rumble of thunder, to locales
primarily along and north of the Highway 82 corridor this morning as
it skims that area.
As the day progresses, the front will begin to make its push into
the region as a mid/upper shortwave slides east out of the nation`s
mid-section, and towards the Southeast United States. This will
allow for a chance of showers, and possible a thunderstorm or two,
to exist across the forecast area today. Once again, the better
storm potential looks to be across Southeast Mississippi where the
better instability will exist this afternoon. Some heavy downpours
will again be possible due to the deeply moist airmass over the
region, but confidence in any severe storms remains quite low. Highs
this afternoon will range from the upper 80s to lower 90s.
Rain chances will gradually come to an end through the evening, but
I`ll linger them for a few hours into the tonight period as high-res
models indicate another weakening disturbance perhaps shifting into
northern parts of the CWA behind the front. Clouds will clear out
through the overnight hours as high pressure and slightly drier air
begins to filter into the region. Lows tonight will range from the
upper 60s to lower 70s.
Ridging aloft and high pressure at the surface will continue to
increase their presence across the region Monday into Monday night.
Under mostly sunny skies with northerly winds, highs Monday
afternoon will warm into the low and middle 90s with noticeably less
humid conditions. Lows Monday night under clear skies will range
from the mid 60s to around 70. /19/
LONG TERM...Tuesday through Saturday...Dry weather will occur
through much of the week as the region remains under the influence
of an 592dm upper level ridge that extends across the south from
north Texas. This ridge will also help temperatures warm into the
lower to mid 90s through Thursday. However, thanks to drier air that
filtered into the region behind Sunday`s trough and frontal passage,
conditions should feel a little better. PW values through Thursday
should be around or just under an inch across the region, and
dewpoints are expected to be in the 60s(even some lower 60s/upper
50s in some parts of the area at times).
The upper ridge will begin to weaken Thursday and southerly flow
will return to the region. This will once again help to bring
moisture back into the region. Precipitable water and dewpoints will
increase from the southeast through the end of the week. This may
help generate some diurnal showers Friday afternoon in the southeast
if there is enough moisture return to combine with daytime heating.
Both the GFS and ECMWF are in decent agreement in a trough swinging
across the western part of the United States by the end of the week.
This trough will push toward the ArkLaMiss region through the
weekend. Ahead of this, showers will be possible, particularly
across the western part of the CWA. Eastern parts of the area may be
inhibited some by higher heights, but some showers will be possible
areawide Saturday. This system does hold some promise that fall-like
weather is on the way. This trough will swing through the ArkLaMiss
beyond the forecast period(Sunday into Monday), but much drier air
and cooler temperatures are possible behind this system as both
models show the upper level trough wrapping into a large low across
the Midwest. There may be hope that fall won`t be long after the
Autumnal Equinox. /28/
&&
.PRELIMINARY POINT TEMPS/POPS...
Jackson 90 71 92 68 / 22 11 5 0
Meridian 89 70 93 68 / 20 13 6 0
Vicksburg 93 70 94 68 / 16 9 3 0
Hattiesburg 89 72 92 70 / 21 13 8 4
Natchez 88 72 91 70 / 13 8 4 0
Greenville 92 69 94 67 / 21 21 2 0
Greenwood 91 69 93 67 / 26 15 3 0
&&
.JAN Watches/Warnings/Advisories...
MS...None.
LA...None.
AR...None.
&&
$$
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
1101 AM CDT SUN SEP 18 2016
.UPDATE...
Issued at 1101 AM CDT Sun Sep 18 2016
Morning fog did burn off as expected. Area of debris cloudiness
associated with MCS now moving across Arkansas should move off to
the east by early this afternoon leaving mainly sunny skies across
the area. RAP soundings are showing mixing up to 900-850mb this
afternoon which should result in highs in the lower-mid 80s. Still
may be some isolated showers over the far southern part of the
eastern Ozarks where there surface observations is showing some
weak convergence, but coverage should be limited.
Britt
&&
.SHORT TERM... (Through Late This Afternoon)
Issued at 301 AM CDT Sun Sep 18 2016
With surface ridge over region, winds are light and plenty of low
level moisture. So patchy fog developing early this morning reducing
visibilities to less than a mile at times, mainly for areas along
and south of I-70. Conditions to improve by mid morning with partly
to mostly sunny skies and temps warming up into the low 80s. Some
activity to develop just south of forecast area on periphery of
surface ridge by this afternoon that could move northeast into
forecast area, so added slight chance pops to far southern portions.
Byrd
.LONG TERM... (Tonight through Saturday)
Issued at 301 AM CDT Sun Sep 18 2016
(Tonight - Tuesday)
Period continues to look dry and warm. Sfc ridge will continue to
build ewd tonight as the upper trof pushes east and upper flow
becomes wly. Upper ridge will build into the region thru Tues, which
shud suppress precip chances. However, an upper trof will move
across srn Canada and the Northern Plains into the Great Lakes Mon
into Mon night. The associated sfc cdfnt is progd to drop into srn
IA and central IL.
With very strong low level WAA ahead of the fnt, much of the area
shud remain capped with warm nose centered around 800mb. However,
given the proximity of what shud be ongoing convection Mon afternoon
and eve as well as potential for elevated convection later in the
night, have kept low PoPs for nrn portions of the CWA.
As for temps, for tonight, have made only minor changes to the prev
forecast. While winds will become sly, low lying areas across the
ern Ozarks shud still decouple allowing temps to drop into the 50s.
Given the warm 850 mb temps between 18 and 22C on both Mon and Tues,
have trended aoa the warmest guidance both days. More uncertainty
exists on Tues for nrn portions of the CWA as the cdfnt pushes swd.
(Wednesday - Saturday)
The CWA is still expected to remain on the nrn edge of rather strong
upper ridge. This will allow warm temps to continue thru much of
the period with little chance for precip until next weekend.
Based on heights across the region, going forecast is probably too
cool, but have kept a persistence forecast going for now. More
questions remain for temps on Sat ahead of an approaching closed low
system. Believe mdls prog this system moving ewd too quickly as is
generally the case for this type of system with the GEFS mean
suggesting a more likely soln. However, will trend closer to climo
for temps on Sat for now.
Have low chance PoPs for Sat as the cdfnt approaches the region for
now, although, as mentioned above is probably on the fast side.
Tilly
&&
.AVIATION... (For the 12z TAFs through 12z Monday Morning)
Issued at 703 AM CDT Sun Sep 18 2016
Patchy fog affecting taf sites through 13z. Then will see VFR
conditions with light south winds becoming southeasterly by this
evening.
SPECIFICS FOR KSTL:
Patchy fog mainly affecting KSUS and KCPS through 13z. Then will
see VFR conditions with light south winds becoming southeasterly
by this evening at all metro area taf sites.
Byrd
&&
.CLIMATE...
Issued at 301 AM CDT Sun Sep 18 2016
Record highs for 19 and 20 September
Date Record Year
UIN 19 95 1972
20 95 1940
COU 19 94 2000
20 98 1893
STL 19 96 1955
20 96 1940
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Marquette MI
722 AM EDT SUN SEP 18 2016
.SHORT TERM...(Today and tonight)
Issued at 453 AM EDT SUN SEP 18 2016
Water vapor loop and latest RAP analysis shows a weakening shortwave
trough ne of Lake Superior moving slowly east through Ontario early
this morning. Focus for weather tonight into Monday shifts to a
complex of shortwave energy from the Pac NW to the Northern Rockies
which will approach the Upper Great Lakes in a zonal flow aloft over
the northern CONUS.
Today: Weakening shortwave ne of Lake Superior and assoc weak 700-
300 mb q-vector convergence could continue to support clouds and
isold shra over the far ern cwa this morning before shortwave
ridging and q-vector divergence/assoc subsidence spreads in from the
west in the afternoon. Otherwise look for generally clearing skies
and dry conditions across much of the area. Warm advection southwest
flow and mixing 85h temps of near 11C east to 14C west to sfc
should yield highs today in the low to mid 70s, warmest west half.
Tonight: Shortwave energy moving eastward along the Canadian border
will push a cold front across the Upper Lakes late tonight and early
Monday. While moisture will be somewhat limited and deeper moisture
will stay farther north, model consensus indicates there should be
sufficient forcing from shortwave and convergence along the front to
squeeze out isold to scattered showers mainly over the north half of
the area tonight closer to the better shortwave dynamics, better
isentropic ascent and deeper moisture with system. NAM model sounding
also show a few hundred j/kg of elevated CAPE across the northern
zones which will also warrant a mention of thunder. SPC has far wrn
cwa under a marginal risk for severe tonight, but given limited
instability and skinny elevated CAPE sounding profiles not expecting
any severe despite increase in deep layer shear. Expect lows generally
in the upper 50s to the lower 60s with the warmest readings along the
Great Lakes shorelines.
.LONG TERM...(Monday through Saturday)
Issued at 444 AM EDT SUN SEP 18 2016
Progressive pattern to begin the long term will give way to an
increasingly amplified pattern this week into next week. This will
occur as a ridge/positive height anomaly shifts into the Gulf of
Alaska/western Canada by mid week, forcing a deepening trof over the
western CONUS and ridging over much of the eastern CONUS. The
magnitude of the positive height anomaly at 500mb will increase to 3
standard deviations above the long term late Sept avg as it shifts
across the Northwest Territories to Nunavut late this week.
Underneath this strong positive height anomaly, the western CONUS
trof will only slowly progress eastward. Some recent GFS/ECMWF runs
show this trof deepening and closing off into a potentially large
mid level low over the Upper Mississippi Valley/Great Lakes region
early next week. If so, an unsettled, chilly period may be in the
offing just over a week from now. Until then, above normal temps
will prevail for the next few days before trending close to normal
mid and late week. As for pcpn, complex of shortwave energy racing e
along the U.S./Canada border region may result in some pcpn tonight
into Mon. After a dry day Tue, frequent rain chances will return Wed
thru Sun. However, if se Canada troffing is strong enough in
response to the western Canada ridge, baroclinic zone/frontal
boundary may be pushed far enough s to allow for a period of dry
weather later this week. That said, the overall look of the pattern
could support the potential of mdt to hvy rain at times as abundant
deep layer moisture will be avbl in the vcnty of a wavering sfc
frontal boundary setting up from the northern/central Plains to the
Great Lakes. As a result, although little pcpn will occur over the
next few days, pcpn amounts for this 7 day period should end up
above normal, potentially well above normal.
Beginning Mon, cold front and band of deep layer forcing associated
with shortwave energy reaching the area late tonight will shift e of
the area by Mon aftn. So, any isold/sct shra/tsra over the e half of
the fcst area in the morning should exit by aftn. As has been the
case over the last few days, some model guidance still show the
potential of a few -shra streaking across the area in the aftn in
association with trailing shortwave energy and a band of mid level
fgen. Given the relative dryness of the air mass following fropa,
pcpn seems unlikely with the exception of the far eastern fcst area
where boundary layer moisture will still be elevated into the aftn.
Included schc pops later in the aftn in that area. With skies
becoming mostly sunny, tight pres gradient/deep mixing will result
in breezy conditions developing, particularly over the w half where
most sunshine is expected. Winds will be strongest over the Keweenaw
with fcst soundings showing potential to mix to 40kt winds aloft,
raising the possibility that a wind advy may be needed. It will be a
warm day with fcst soundings suggesting max temps well into the
70s for much of the area.
With a deep dry air mass over the area, dry weather is expected Mon
night/Tue. Despite clear skies and pwat falling to 0.4-0.5 inches
Mon night, temps won`t fall as much as would be possible due to
relatively tight pres gradient with 925mb winds remaining mostly in
the 20-35kt range. Traditional interior colds spots over the w half
could slip toward 40F. Temps will range up well into the 50s to near
60F across the n where low-level wind fields will be strongest.
Winds will still be on the breezy side Tue with fcst area btwn sfc
high pres ridge to the s and sw and deep low pres over Hudson Bay.
Winds will again be strongest on the Keweenaw, but not as strong as
Mon. With sunny skies at least into early aftn, highs on Tue will
top out mostly in the lower to mid 70s with dwpts down into the 40s
away from lake moderation.
Trof that will be amplifying into the western CONUS Tue/Wed will
pick up energy off the southern CA coast and send it ne, reaching
the western Great Lakes Wed evening. With pwat surging up to 1.5
inches and assistance of upper divergence associated with right
entrance of upper jet across northern Ontario/Quebec, expect shra to
overspread the area Wed aftn/night.
A couple of days ago, medium range models began to indicate the
possibility of sufficient troffing developing over se Canada in
response to the western Canada ridge to allow sfc high pres ridging
to build se into the Upper Lakes Thu and potentially thru Fri. The
signal has not been consistent since then, but 00z medium range
models are in better good agreement on this scenario, which seems
reasonable based on the strength of the positive height anomaly
shifting into n central Canada. In addition, there appears to be
decent support from the Canadian and especially the GFS ensembles
for this evolution. If correct, baroclinic zone/frontal boundary may
shift far enough s to mostly end pcpn chc across the fcst area later
Thu into Fri. Since consistency on this idea has yet to solidify on
multiple model runs, fcst will still maintain some pops both days,
especially across the s.
Pcpn chances should increase over the upcoming weekend as the
western trof slowly approaches. However, significant spread develops
among the GFS and Canadian ensembles with some not even moving the
trof to the Great Lakes region. With the uncertainty, a simple model
consensus was utilized for the fcst Sat/Sun.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 712 AM EDT SUN SEP 18 2016
Clearing skies have allowed patchy fog and stratus to form at TAF
sites early this morning. Expect IFR to MVFR conditions to lift to
VFR by late morning as diurnal mixing scours out fog/stratus. The
approach of a cold front will bring in mid-level clouds and some
isolated shra to the western taf sites by late evening/overnight.
Will carry a mention of VCSH at IWD and CMX to cover this. Also
increasing SW winds ahead of the front will result in LLWS overnight.
&&
.MARINE...(For the 4 AM Lake Superior forecast issuance)
Issued at 433 AM EDT SUN SEP 18 2016
Winds will remain generally below 20 kts today into this evening.
Tightening pres gradient between high pressure area over the Plains
and low pressure tracking through northern Manitoba toward Hudson
Bay will cause SW winds to increase as high as 25 knots late tonight
and to 30 knots on Monday as shift wsw in the wake of the cold front
associated with the Canadian low. In fact, there could be a period
of gale gusts to 35 knots between Isle Royale and the Keweenaw
Peninsula late Monday morning into the afternoon hours as west-
southwest winds will become enhanced by channeling between these
features. West winds should generally diminish to 25 knots Mon night
into Tue as gradient slackens with Canadian low lifting farther ne
across Hudson Bay. Winds will diminish to less than 20 kts
Wednesday into Friday under weak pres gradient across the Upper
Lakes.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Voss
LONG TERM...Rolfson
AVIATION...Voss
MARINE...Voss
Area Forecast Discussion
National Weather Service Paducah KY
725 AM CDT SUN SEP 18 2016
.SHORT TERM...(Today through Tuesday night)
Issued at 324 AM CDT Sun Sep 18 2016
Models show a weak upper level trof moving across the PAH forecast
area this afternoon. GFS keeps us dry, while ECMWF and HRRR generate
some light QPF mainly west of the Mississippi River this afternoon.
Included some slight chance pops for showers for a portion of our
southeast Missouri counties from 17z to 23z to account for it.
Despite northerly winds and some cloud cover, temperatures will be
a bit above seasonal normals today and tonight. Highs will be in
the lower to middle 80s with lows in the 60 to 65 degree range.
For tonight into Monday, surface high pressure will be sliding
east across our region. Winds will shift back to the south, and
temperatures will warm a few more degrees for Monday into Tuesday
night. Models show a weak cold front moving into the middle
Mississippi and lower Ohio River valleys Tuesday and washing out
Tuesday night. Models keep us dry, and the only result will be
light winds shifting to the north Tuesday night.
.LONG TERM...(Wednesday through Saturday)
Issued at 324 AM CDT Sun Sep 18 2016
Above average confidence through most of the period, then average
to below average at the very end due to slight model inconsistencies.
Still very little to discuss and very few changes synoptically
through most of the long term period. High pressure at the surface
and ridging aloft is forecast through most of the long term period
producing dry, warm, and humid conditions.
Friday night the GFS continues to weaken and suppress the upper
ridge slightly southward allowing a back door cold front to sag into
the far northern and northeastern sections of our CWA on Saturday.
In the process it also cranks out a few hundredths of QPF over the
same areas.
During the same time frame the ECMWF weakens the ridge but shows
deeper moisture and small precipitation chances over the southern
and western sections of our CWA on Saturday. The latest Superblend
model run appears to be picking up on that so will just go with
that which indicated slight chances area wide.
Temperatures will remain at or above normal through the period.
&&
.AVIATION...
Issued at 725 AM CDT Sun Sep 18 2016
Any lingering LIFR cigs/vsbys will improve to VFR by 14z. VFR
conditions are then expected through 08z, then MVFR vsbys are
possible. Winds will be light and variable, becoming calm after
00z.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
SHORT TERM...RST
LONG TERM...JP
AVIATION...RST
Area Forecast Discussion
National Weather Service Tallahassee FL
1016 AM EDT SUN SEP 18 2016
.NEAR TERM [Through Today]...
The 7 am regional surface analysis showed a weak ridge along the
Piedmont, and a weak cold front from western TN to the Red River.
Vapor imagery and upper air data showed a weak short wave trough
over Al and the northern Gulf of Mexico, and a potent short wave
trough translating quickly eastward over the Central Plains.
Satellite imagery showed precip water values 20-50% above average
over the western half of our forecast area, and the latest RAP
showed weak Q-G forcing here as well.
Isolated showers were occuring across this region, especially
over the coastal waters. However, we expect enough breaks in the
clouds late this morning to allow strong insolation to drive the
FL sea breeze engine. This mesoscale forcing, combined with other
mesoscale boundaries farther inland, will combine with the
favorable synoptic environment to produce ample deep moist
convection across much of our forecast area this afternoon and
evening. The high amount of moisture throughout the column
suggests the likelihood for high rain rates. Fortunately there
does appear to be just enough steering flow (10 kt 850-500 mb) to
prevent stalled storms, but there could be a few exceptions to
this rule. Thus our main focus today in terms of hazardous weather
will be localized flooding, as unimpressive CAPE and shear values
should limit the threat of severe storms.
&&
.PREV DISCUSSION [829 AM EDT]...
.SHORT TERM [Tonight Through Tuesday]...
By tonight a northern stream trough will cover much of the eastern
CONUS, with its axis stretching from the Great Lakes, through the
Ohio Valley, and entering the Tennessee Valley. At the surface, a
frontal boundary will lie just ahead of the upper trough axis,
essentially down the spine of the Appalachians. Through Tuesday,
the southern half of the trough will separate and become entangled
with the remnants of Julie off the Southeast/Mid-Atlantic coasts
while the northern half lifts through the Northeast. Little
movement is expected with the southern system once Julie phases
with the upper wave, thus the attending surface front will likely
stall across the Southeast, possibly bisecting the Tri-State
region.
Expect numerous showers and thunderstorms along and ahead of the
front on Monday, with the highest PoPs east of a line from Albany
through Panama City. On Tuesday, the only chance for rain will be
slight and confined to the southeast Big Bend as a large area of
subsidence and dry air overspreads much of the region. As far as
temperatures are concerned, highs will be near normal on Monday
and maybe a degree or so above on Tuesday. Lows will fall into the
lower 70s, which is a few degrees above normal.
.LONG TERM [Tuesday Night Through Sunday]...
While ridging will try to build into the region, the extratropical
system that was Julie will continue to meander over the southern
Eastern Seaboard into to the weekend. As the system drifts
westward a bit late in the week, rain chances will increase once
again. There will likely be a sharp west/east delineation of PoP
coverage that will depend upon just how far west the
aforementioned system drifts. High and low temperatures will be
near to slightly above average.
.AVIATION [Through 12Z Monday]...
It took until after sunrise, but VLIFR cigs, and even some areas
of MVFR- IFR Vis were rapidly developing across the region.
Conditions will improve to VFR by late morning. Isolated TSRA were
occuring along the Panama City beaches, but will likely dissipate
by late morning. However, numerous TSRA will develop this
afternoon and affect most of the terminals.
.MARINE...
Light winds and low seas will prevail outside of thunderstorms for
the next several days. The best chances for rain will continue to
be overnight and through the day on Monday as a front nears the
northeast Gulf.
.FIRE WEATHER...
No hazardous fire weather conditions expected for the next several
days.
.HYDROLOGY...
Average rainfall amounts over the next several days will be around
an inch, with locally higher amounts between 2-3 inches possible.
These totals will mostly fall today through Monday. These forecast
amounts are not expected to cause any widespread or significant urban,
rural, or river flooding.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 89 75 91 74 93 / 60 20 40 20 20
Panama City 86 77 86 76 89 / 40 30 40 10 10
Dothan 88 72 92 70 92 / 60 40 10 10 10
Albany 89 73 93 71 93 / 60 40 20 10 10
Valdosta 89 72 89 71 91 / 40 30 60 20 20
Cross City 89 73 88 73 90 / 40 20 60 30 20
Apalachicola 85 76 86 75 88 / 30 30 50 20 20
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...Fournier
SHORT TERM...Harrigan
LONG TERM...Harrigan
AVIATION...Fournier
MARINE...Harrigan
FIRE WEATHER...Barry
HYDROLOGY...Harrigan
Area Forecast Discussion
National Weather Service La Crosse WI
600 PM CDT Sun Sep 18 2016
.SHORT TERM...(This evening through Monday)
Issued at 248 PM CDT Sun Sep 18 2016
Main forecast concerns in the short term are on Thunderstorm chances
tonight and again late Monday afternoon into Monday evening.
Isolated to scattered thunderstorms are possible late tonight into
Tuesday as a cold front marches southeast across the region. The
nose of the best 850 mb moisture transport and upper level forcing
are across northern Wisconsin tonight. Therefore, will keep the
highest chances for showers and storms confined to mainly Taylor and
far northern Clark counties. The RAP forecast sounding at MDZ
indicates around 1300 J/KG CAPE by 08Z tonight with 1-6 KM Bulk
Shear values of 25 kts. Cannot rule out a strong storm or two with
the potential for large hail. Better shear noted across northwest
Wisconsin so thinking these areas stand a higher chance of seeing
some large hail if storms develop.
The cold front marches through the areas during the day on Monday
and thunderstorms most likely won`t develop along it until its in
far southern Wisconsin. The delay in thunderstorm development is
from a strong cap in place. Thunderstorms could initiate along the
front between 20 and 23Z. The main area we will really have to
watch is Grant County in far southwest Wisconsin and possibly
Clayton County in northeast Iowa, where the storms could initiate.
It appears the storms will develop just south and east of the
forecast area. The storms will probably be supercells initially with
SBCAPE values of 2500 j/kg and 0-6 km bulk shear of 45 to 50 kts.
They may form into line segments too with 0-3 km bulk shear of 30 to
35 kts.
.LONG TERM...(Monday night through Sunday)
Issued at 248 PM CDT Sun Sep 18 2016
Main forecast concerns in the long term are on flooding potential
starting late Tuesday night through Thursday with periods of heavy
rainfall possible.
High pressure builds in Monday night into Tuesday with light wind
and mostly clear skies expected. This will set the stage for areas
of fog, especially along river valleys and central Wisconsin. Will
be adding fog to the forecast form late Monday night into Tuesday
morning. The high quickly shifts off to the east Tuesday afternoon
into Tuesday evening as low pressure develops across the plains. A
warm front is expected to lift into the Upper Mississippi River
Valley Tuesday night with Thunderstorms developing along it.
Moisture will be quick to return on southerly flow with precipitable
water values climbing into the 1.5 to 1.9 inch range. Warm cloud
depth increases to 3.5 to 4.0 km too. 850 mb moisture transport
increases into the region as the low level jet ramps up with
Moisture Transport Vector magnitude of 250 to 400 and is focused
into the warm front. This will set the stage for a possible flash
flood situation. Confidence was not high enough on where the feature
will setup to issue a watch but one may be needed soon if model
trends continue. The heavy rain environment remains in place through
the day on Wednesday the ramps up again Wednesday night into
Thursday morning. This second overnight round of heavy rain
Wednesday night may focus just a little further north that the first
round. If both rounds of heavy rain fall over the same area, a
serious flooding situation may evolve. Considering the local area is
over 200 percent of mean precipitation for the past 30 days, the
soils are nearly saturated. A lot of uncertainty at this time on
where the heaviest rain will be so continue to monitor later
forecasts closely.
Thursday through Sunday
Good model agreement that precipitation will be ongoing at the
beginning of this period, as a warm front and shortwave trough work
through the area. Widespread precipitable water values over 1.5
inches and warm cloud depths near 4 km point to yet another heavy
rain event. Following the shortwave, the boundary stalls over the
region while a closed low over the Dakotas continues to bring
moisture into the area allowing precipitation to last into the
weekend, which is when the model solutions diverge. The 18.12Z GFS
sends the low northeastward into Canada, quickly moving the cold
front and additional precipitation through the area, while the
18.00Z ECMWF has the low farther south, keeping the area wet for a
bit longer. The 18.12Z ECMWF comes into better agreement with the
GFS regarding the placement of the low, but is still slower in
moving the cold front through. With the region receiving well above
normal precipitation over the last few weeks, a consistent heavy
rain signal like this from the models certainly makes flooding a
major concern.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 600 PM CDT Sun Sep 18 2016
Front and low level warming slated to move eastward across the
region late tonight-Monday morning. Band of mostly mid level clouds
with scattered -shra will accompany the forcing...with the better
rain threat north of the TAF sites. Some hints in a few models that
there could be lower cigs...but going to stick with VFR for now. Sfc
front should fire shra/ts later Monday afternoon, but will have
moved far enough east/south that there shouldn`t be an impact for
KLSE/KRST.
LLWS an issue for both TAF sites tonight, even if decoupling is
limited. HRRR/RAP/NAM bufkit soundings all suggesting mid 40 kts
before 2 kft for much of the night time hours. Will continue to
carry mention for KRST/KLSE. Weakening pressure gradient/flow will
lead to lessening winds Monday morning, along with a shift to the
west/northwest as the front slides through.
&&
.HYDROLOGY...Tuesday night into the weekend
Issued at 248 PM CDT Sun Sep 18 2016
Flooding possible this week. Periods of heavy rainfall are possible
starting Tuesday night persisting into Thursday. Thunderstorms
could develop and repeat or train over locations starting late
Tuesday night and persisting into Thursday. With soils nearly
saturated at many locations, flash flooding is possible. In
addition flooding may develop on area rivers and this flooding
could persist through late week into the weekend. Flood watches
may be issued once confidence increases on where the heaviest rain
will be. Also, more heavy rain is possible later in the week going
into the weekend, making any flooding issues worse. Monitor
forecasts closely over the next few days.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...DAS
HYDROLOGY...WETENKAMP
Area Forecast Discussion
National Weather Service Columbia SC
204 PM EDT SUN SEP 18 2016
.SYNOPSIS...
A weak cold front moving into the forecast area will merge with low
pressure off the southeast coast Monday. A trough will linger near
the coast through much of the week and a chance of showers and
thunderstorms will continue.
&&
.NEAR TERM /THROUGH TONIGHT/...
A surface ridge across the Upstate and NC Piedmont will weaken
today as the parent high pressure over the Atlantic moves further
east. The upper level ridge over the area will give way to an
approaching upper trough and associated cold front which will
enter the area Monday.
As the surface ridge weakens during the day, models indicate an
increasingly easterly mid-level flow. This may work to moisten
the relatively dry air and PWAT values currently around 1.6
inches. Weak convergence into the ridge and daytime heating have
produced a cumulus field over the area. Current satellite and
radar returns indicate an area of enhanced cumulus and weak
showers/virga in the eastern Midlands. Increasing moisture and
weak to moderate instability may not be enough to initiate deep
convection over much of the area with a mid-level capping
inversion in place and only weak surface forcing. Widely
scattered to isolated diurnal convection will be possible along
the eastern Midlands where the best mid and low level moisture is
present.
Late this afternoon and evening, a shortwave ahead of the upper
trough will move into the CSRA and Midlands. Increasing moisture,
upper level support and surface convergence will prolong showers
and thunderstorms as they move eastward from central GA. HRRR
trends indicate an increasing chance of convection lingering into
the evening, however should dissipate late this evening. With
increasing cloudiness limiting radiational cooling, expect lows
around 70 degrees into the low 70s tonight.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
The weak front will be near the forecast area Monday. There
should be little convergence associated with the front because of
the northwest low-level flow on the backside of offshore low
pressure. The models depict the upper trough moving into the
forecast area becoming a cut-off low by Monday night with this
feature lingering through Tuesday. Instability and moisture
associated with the upper system should help support showers and
thunderstorms. There may also be increased moisture Tuesday in the
flow wrapping around offshore low pressure. The models have not
been consistent with the timing and placement of this moisture. We
used an average of the guidance and forecasted chance pops. The
NAM and GFS depict moderate instability Monday with surface-based
LI values -5 to -7 indicating a possibility of thunderstorms with
strong wind and hail although that threat should be limited by a
lack of significant low-level convergence and the models may be
overdone with the instability forecast because of expected
cloudiness. Followed the guidance consensus for the temperature
forecast.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
The GFS and ECMWF show the h5 low remaining over the area with a
surface inverted trough near the coast through Thursday or Friday.
The models display the surface feature weaker with the upper low
opening and lifting northward by Saturday. However, another
frontal system may approach Sunday. The GFS and ECMWF MOS support
chance pops through the period. The MOS has been trending downward
with high temperatures Tuesday through Thursday with increased
cloud cover and a northeast flow.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Light and variable winds expected for much of the period. There is
a chance for isolated diurnal convection this afternoon, mainly
in the eastern Midlands. Current satellite and radar images
indicate an area of enhanced cumulus and weak showers/virga in
the extreme eastern Midlands. With coverage limited and doubt as
to whether showers are reaching the ground, have left VCSH/SHRA
out of OGB TAF. Later this afternoon, an upper disturbance will
move into the CSRA which may help support showers and
thunderstorms as they move eastward from central GA. Although
relatively dry air and loss of daytime heating should help
dissipate storms through the early evening.
Skies will become mostly cloudy as a weak cold front moves into
the area Monday. Restrictions will be possible early Monday
morning with the threat of convection picking back up near the end
of the TAF period.
EXTENDED AVIATION OUTLOOK...Models keep moisture over the region
through the remainder of the week, keeping in the chance for
mainly diurnal showers and thunderstorms.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
&&
$$
SYNOPSIS...99
NEAR TERM...99
SHORT TERM...99
LONG TERM...99
AVIATION...99
Area Forecast Discussion
National Weather Service State College PA
603 PM EDT SUN SEP 18 2016
.SYNOPSIS...
A deep plume of moisture will provide for clouds and showers this
afternoon into Monday until the weak upper trough moves to our
east Monday. A large ridge to our southwest will slow provide
above normal heights and temperatures to the region. Most of the
week will be dominated by this ridge. This should produce a
stretch of relatively dry weather with above normal and summer-
like temperatures peaking later in the week.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
Clouds continue to stream from southwest to northeast over the
State this afternoon. A deep moisture plume is moving into the
region with the clouds and the enhanced deep moisture on WV
imagery.
The HRRR and NCEP models continue to focus rain over central PA
with showers and isolated thunderstorms moving SW to NE over the
region. Very unorganized in HRRR and radar has been less robust
then HRRR forecasts today. The first band of rain brought light
rain to Clearfield County and is moving mostly unnoticed across
central areas.
The rain area in WV with the deeper moisture should move into
southwestern PA later this afternoon and evening. HRRR has it in
Somerset County by 4 PM. The probability of rainfall will increase
in SW PA this afternoon and this increased chance should move to
the north and east this evening.
Most areas will be mostly cloudy to cloudy this afternoon and
evening with higher threat of rain this evening and early tonight.
It will be warm and humid this afternoon and this evening. The
HRRR thinks that most of southeastern PA will remain dry this
forecast period.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH MONDAY NIGHT/...
The HRRR implies some organized convection develops after midnight
in East-central PA. Favoring some overnight rain and
thunderstorms. Far more focused and locally organized than the
GEFS/NAM show.
The higher probability of rain/showers shifts eastward fast this
forecast period and rain should end in the eastern areas. Though
the moisture and high moisture will lead to areas of fog and dense
fog. Rain lingers into late morning in southeast.
Fog and low clouds may be slow to lift out in west/central but
POPS are low in morning and the sun should work its way out Monday
generally from west to east. The southeast will likely have to
wait until the afternoon. But the day should end on a drier note
with some sun in the afternoon and evening.
Slightly cooler but noticeably drier overnight Monday into
Tuesday. Expect some overnight fog to develop.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
High pressure building in from the Ohio Valley will bring some
valley fog early Tuesday, followed by dry weather for the midweek.
A cold front over the north-central part of the country will run
into rising heights aloft as it slides toward the northeast
Tuesday, with showers evaporating as they approach. Well-above
normal temperatures (on the scale of 8-10F above normal) will
bring highs back into the upper 70s to mid 80s as anomalously high
upper heights (588-590dm at 5H) peak.
Heights don`t really fall back all that much heading into the
weekend as a large trough forms over the Rockies keeping the
ridge in place. Bit of a back-door cold front slides through on
Sat, though "cold" front may be an overstatement. Just a slight
chance for showers and a push of somewhat cooler air will nudge
temps back down toward seasonal norms. Latest guidance builds high
pressure into the region from the Great Lakes for late
weekend/early next week as sharp ridge builds aloft. So chances
for significant precip during this period remain quite low.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
Regional radar loop at 22Z showing sct showers and few tsra across
central Pa in advance of a slow moving cold front over eastern
Ohio. Conditions predominantly VFR as of 22Z, but continued
showers, combined with nocturnal cooling of boundary layer, should
result deteriorating cigs/vsbys overnight. Many locations will
likely be IFR or LIFR somewhere near the 08 to 13Z time range
Monday morning.
The drier air clears the region during the day Monday west to east
so a slow change from IFR to MVFR during the day.
Outlook...
Mon-Thur...AM valley fog possible,otherwise, no significant
weather.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Grumm
NEAR TERM...Grumm
SHORT TERM...Grumm
LONG TERM...RXR
AVIATION...Grumm/Fitzgerald
Area Forecast Discussion
National Weather Service Grand Forks ND
327 PM CDT SUN SEP 18 2016
.SHORT TERM...(This evening through Monday)
Issued at 327 PM CDT Sun Sep 18 2016
An upper wave is currently moving through ND/MB...with drying
noted in water vapor imagery across central ND. A surface trough
lies in the Red River Valley...extending south from surface low in
Manitoba. Temps have risen to 77-81 in the Cando-Devils Lake-
Langdon area where westerly winds and more sun have prevailed.
Seeing low/mid 70s across much of the RRV and upper 60s/low 70s
further east in Bemidji to Lake of the Woods country. Believe
we`ll still see some more warmth push east as the trough
progresses eastward and clouds start to diminish late this
afternoon.
Still could see a thunderstorm or two in the north...closer to the
Canadian border with the main upper wave late this afternoon and
this evening. A few older runs of the HRRR tried to bring in some
precip to the Fargo area this evening. Latest HRRR has dropped
that although 18Z NAM still has a blip. Will keep it dry that far
south for now. Clouds will diminish and a weak cold front will
pass through the area tonight. But with westerly winds...lows
should only dip to the low 50s across the area.
Monday...the large surface low will be over Hudson Bay and high
pressure will be over Nebraska...giving westerly winds to the area
under sunny skies. Temps are expected to range from the upper 60s
northeast (Lake of the Woods) to mid 70s southwest (across SE ND).
.LONG TERM...(Monday night through Sunday)
Issued at 327 PM CDT Sun Sep 18 2016
The beginning of the long term will bring the end of the quiet
weather before a fairly active period commences. Upper level zonal
flow will continue with broad high pressure in place across the
upper Midwest. Monday night will see temperatures right around
normal values as clear skies give way to clouds moving in from the
west towards morning. The ECMWF depicts an area of QPF along and
south of I-94 on Tuesday while the other models remain dry.
Therefore, continued with a dry forecast with low confidence of
anything actually occurring. Although the area could see limited
sunshine, high temperatures should be able to get up into the upper
60s across the north and maybe the mid 70s in the south.
The pattern will then transition to southwest flow aloft as a strong
upper low deepens across the Pacific Northwest. This system is
progged to makes its way towards the four corners region midweek,
then head northeast towards the Dakotas by the weekend, providing
the area numerous chances for precipitation throughout the remainder
of the period.
The first appreciable wave looks to impact mainly the southeastern
half of the forecast area on Wednesday. Models are coming into
better agreement with a brief period of upper ridging building in on
Thursday so tried to cut back PoPs a bit for this time frame. Friday
into Saturday will bring the best chance for widespread
precipitation as the upper low deepens across the northern Rockies
and propagates towards the forecast area. As the low wraps up just
north of the border, much of the area could see decreasing chances
for precipitation for the second half of the weekend as a dry slot
works northward. This will need to be watched to try and pinpoint
the best areas/timing for precipitation as the event draws nearer.
Throughout the majority of the period, especially late in the work
week and weekend, the bulk of any instability looks to be across
South Dakota and southern Minnesota. Therefore, continued with the
previous thinking of mainly rain showers, except for a few rumbles
of thunder here and there during the daytime hours.
After a fairly mild Tuesday, the rest of the period will see
slightly cooler temperatures with highs generally ranging from the
mid to upper 50s across the north and mid to upper 60s in the south.
The good news is that it should be awhile before another
frost/freeze threat across the area with lows expected to remain in
the 40s and 50s.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1256 PM CDT Sun Sep 18 2016
VFR conditions expected across the area today. Could see some
gusts to 25-30kts this afternoon however. A few showers or
thunderstorms are possible near TVF or BJI this evening.
Probability is very low so kept out of TAF ATTM.
&&
.FGF Watches/Warnings/Advisories...
ND...None.
MN...None.
&&
$$
SHORT TERM...Knutsvig
LONG TERM...Lee
AVIATION...Knutsvig
Area Forecast Discussion
National Weather Service Fort Worth TX
335 PM CDT SUN SEP 18 2016
.SYNOPSIS...
Generally unseasonably hot and dry conditions are forecast
through a majority of the work week as high pressure settles in
across the region. Low rain chances will return on Friday with
better rain chances and cooler temperatures expected for next
weekend.
&&
.SHORT TERM (Tonight through Tuesday)...
Visible satellite imagery this afternoon revealed a mostly stable
atmosphere across North and Central TX with mostly fair weather
cumulus. The exception to this is across portions of eastern and
southern zones where afternoon CU looks a bit more robust. While
the overall potential for additional convection looks low at this
time, I`ll retain a slight chance (20%) of rain down across our
last tiers of counties in southeastern zones. Otherwise, the
remainder of the afternoon should be mostly sunny with light and
variable winds.
For tonight---The upper trough largely responsible for this
morning`s complex of storms is expected to slide southward through
the region resulting in continued large scale subsidence. This
combined with the generally clear skies and ample low level
moisture in place (especially for areas that received rainfall
this morning), should support a patchy fog potential.
Interestingly enough, the usually aggressive HRRR visibility
products only show minor reductions in visibility. As a result,
I`ll only add a mention of patchy fog for areas along the Red
River and across eastern/southeastern zones, where both SREF
reduced visibility probabilities are the highest, forecast
dewpoint depressions are the lowest and where rainfall analysis
indicates measurable precipitation over the past 24 hours.
For Monday and Tuesday---An H5 ridge should settle in across
North and Central TX nicely in the wake of the aformentioned
trough. The subsidence associated with this feature should mean
little in the way of precipitation with just a few patches of
afternoon cumulus. The subsidence will also allow temperatures to
warm around 5 to 8 degrees above normal values for this time of
year with most areas in the mid 90s. A few of the more urban areas
may even see temperatures closer to the upper 90s. With low level
moisture not being scoured out, heat index values will near the
century mark. Individuals that work outdoors should certainly
continue to remain hydrated and take breaks. Overnight low
temperatures will be mild with readings in the 70s. A few
sheltered and low lying areas, especially across northeastern
zones may fall into the upper 60s.
&&
.LONG TERM (Wednesday through Saturday)...
Wednesday and Thursday---Warm conditions are expected to continue
through the mid-week time frame as the mid-level ridge remains in
place. Low level moisture is expected to slowly increase,
especially on Thursday, with the weak southeasterly winds. As a
result, afternoon high temperatures may be tempered by a couple of
degrees. The mid-level ridge should maintain its magnitude and
will be efficient at limiting shower and thunderstorm activity.
Friday through Saturday---Big changes will take shape towards the
end of the work week and into the weekend. A potent upper trough
is expected to shift eastward out of the intermountain west and
into the central plains. The strong flow across the higher terrain
will induce lee-side cyclogenesis. In response,
southerly/southeasterly winds should intensifying late Thursday
into Friday morning. The increasing winds in the boundary layer,
coupled with moisture transport should result in continued mild
conditions. With this in mind, I`ve nudged overnight temperatures
upward above most statistical guidance for Friday morning. With
the mid-level ridge shifting off towards the east in advance of
the upper trough, it`s likely that some diurnally driven
convection will develop, especially across southeastern zones as
the sea-breeze lifts northward. With this in mind and with
agreement among most models, I`ve gone ahead and introduced some
slight chance PoPs across far southern and southeastern zones. Low
level winds should result in breezy and perhaps less oppressive
conditions as afternoon mixing occurs on Friday.
Rain chances will increase across all of North and Central TX on
Saturday as synoptic scale lift overspreads the region. The best
lift is expected to be across western and northern zones and this
is where the highest PoPs (40%) are painted. Good forcing for
ascent will continue through the day on Sunday as the high
amplitude trough slowly nudges towards the east. The ECMWF has
come into a bit better agreement with the latest GFS with regards
to the upper trough. This upper trough should help to drag a
noticeable cold front through much of the region resulting in
continued rain chances into early next week. Temperatures in the
wake of the cold front should fall closer to seasonal averages
with high temperatures in the 80s and overnight lows in the 60s
and 70s. Both the GFS and ECMWF both pinch the main upper level
low off from the stronger westerlies aloft. This could mean that
cooler weather and low rain chances linger even towards the middle
portion of next week, which will certainly be welcomed after the
extended period of above average temperatures.
24-Bain
&&
.AVIATION...
/ISSUED 1220 PM CDT SUN SEP 18 2016/
VFR conditions and light southeast winds will prevail through the
period. Subsidence should eliminate any potential for convection
across North TX this afternoon, but an outflow boundary
positioned across Central Texas may be sufficient to initiate an
isolated thunderstorm or two this afternoon. However, this
activity should be southeast of all area TAF sites including
Waco, hence the lack of any mention in the TAF.
-Stalley
&&
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 76 98 76 97 73 / 5 5 5 5 0
Waco 74 98 73 96 72 / 5 10 5 5 5
Paris 72 96 71 95 69 / 5 5 0 5 0
Denton 73 97 72 96 71 / 5 5 0 5 0
McKinney 73 97 72 96 71 / 5 5 0 5 0
Dallas 77 98 77 97 74 / 5 5 5 5 0
Terrell 74 97 74 95 71 / 5 5 5 5 0
Corsicana 75 97 74 95 72 / 5 5 5 5 0
Temple 73 97 72 96 72 / 10 10 5 5 5
Mineral Wells 72 97 71 95 70 / 5 5 0 5 0
&&
.FWD Watches/Warnings/Advisories...
None.
&&
$$
26/24
Area Forecast Discussion
National Weather Service Jacksonville FL
425 PM EDT SUN SEP 18 2016
...Numerous Showers and Thunderstorms Expected Monday Afternoon...
.Near Term /through Monday/...
Model guidance supports development of widely scattered
showers/isolated t-storms late this afternoon for western/southern
areas...possibly spreading over spine of nrn FL peninsula this
evening before diminishing late...with other activity possibly
moving into our western se GA counties thru the evening. This
shown best by NAM and experimental/improved HRRRx...with
operational HRRR appearing overdone with evening precipitation.
Low temps will be in the lower-mid 70s.
Shortwave trough to move across the area Monday. Moist airmass
will be in place. Anticipate similar weather pattern and
uncertainty regarding the forecast details persists for Wednesday,
with one change in the pattern being a deeper northeast flow. ate
scattered showers/isolated t-storms over our western counties
during the late morning-midday hours...with activity becoming more
numerous during the afternoon while spreading eastward. Will
maintain likely POPs across much of the forecast area. High temps
are expected to be in the upper 80s to around 90.
.Short Term /Monday night through Wednesday night/...
Shortwave trough over the southeastern states will cutoff over the
Savannah River Valley on Monday night and will essentially remain
stationary through Wednesday night. The frontal boundary
associated with this trough aloft will stall over inland
southeast Georgia and the western Suwannee Valley as surface
ridging builds from the Ohio Valley and southern Great Lakes
states eastward into the Mid-Atlantic states. This weather
pattern will create a relatively weak pressure gradient over our
region on Tuesday, with a gradually deepening northeast flow
expected Wednesday as surface ridging to the north of our region
builds down the southeastern seaboard and bridges the frontal
boundary.
Widespread late afternoon convection on Monday will move eastward
into coastal areas by sunset and then into the coastal waters
during the mid evening hours. Some lingering activity cannot be
ruled out in northeast and north central Florida overnight,
especially in coastal areas, as a weak lingering trough axis from
Julia remains situated over our region. Fog may also become a
hazard overnight over inland areas as drier air aloft attempts to
advect into inland southeast Georgia and the Suwannee Valley by
early Tuesday morning, but confidence is not high enough to
include in the forecast grids at this time. Lows will generally
fall to near 70 inland, with mid 70s at the coast.
Quite a bit of uncertainty prevails in the forecast for Tuesday
and Wednesday due to the positioning of the upper trough over the
southeastern states. This feature may advect enough dry air aloft
to limit rain chances over inland southeast Georgia and the
Suwannee Valley, but there will be such a weak gradient that
mesoscale influences such as the sea breeze will trigger scattered
to numerous showers and thunderstorms over north central Florida,
where deeper moisture will be found. Outflows from this convection
will propagate inland by late afternoon, so widely scattered
activity will also be possible over the Suwannee Valley and inland
southeast Georgia. This activity may linger through the early
evening hours over much of northeast Florida as a lingering low
level trough from Julia persists as well. Highs on Tuesday will
climb to near 90 inland, with mid 80s at the coast where the sea
breeze will develop by early afternoon. Lows will again remain in
the 70-75 range.
Deeper northeast flow may bring a few coastal showers onshore on
Wednesday morning, with afternoon convection along the Atlantic
sea breeze moving inland. With the continued uncertainty in
available moisture and limited overall instability, will maintain
model blends of scattered convective coverage for most areas,
except numerous coverage for locations near and west of Lake
George. Highs may run a few degrees cooler than Tuesday, with
Wednesday`s maxes generally in the upper 80s inland and mid 80s at
the coast.
.Long Term /Thursday through Sunday/...
Persistent mid and upper troughing over the southeastern states
on Thursday will gradually fill and retrograde through Saturday as
Atlantic ridging builds westward. A warm and humid weather pattern
will prevail, with easterly low level flow expected on Thursday,
veering to southeasterly on Friday. At least scattered convection
will develop along the Atlantic sea breeze on Thursday and Friday
afternoons, with early afternoon activity along I-95 shifting
inland by late afternoon and early evening. A relatively weak
pressure gradient will prevail next weekend, with scattered
convection again expected along sea breeze and outflow boundaries
as synoptic forcing remains nonexistent. Above climo temperatures
will prevail through next weekend, with highs generally climbing
into the lower 90s inland and mid 80s at the coast. Lows will
generally remain in the 70-75 range.
&&
.Aviation...
Generally VFR conditions expected through this evening. Limited
VCSH to KGNV site. Patchy low clouds and fog possible tonight.
Model guidance not really suggesting the low conditions
experienced this morning. Later shifts will need to monitor the
potential for lower conditions late tonight into early Monday
morning.
&&
.Marine...
East to northeast flow tonight will become more southerly Monday
and Monday night given weak surface trough. Trough will move
across the waters with high pressure building north of the region
Tuesday-Thursday setting up an onshore flow pattern. Wind speeds
will generally be 15 kts or less...with 2-4 ft seas...through the
period.
Rip Currents: Moderate risk ne FL coast this afternoon...Low risk
se GA coast. Low risk expected Monday for ne FL and se GA coast.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 72 90 70 90 / 20 60 20 30
SSI 73 87 74 86 / 10 50 40 40
JAX 73 89 72 89 / 20 60 30 40
SGJ 74 87 74 86 / 20 50 40 40
GNV 72 89 72 90 / 30 60 20 50
OCF 74 89 72 89 / 30 60 20 50
&&
.JAX Watches/Warnings/Advisories...
FL...None.
GA...None.
AM...None.
&&
$$
Wolf/Nelson/Peterson
Area Forecast Discussion
National Weather Service Marquette MI
426 PM EDT SUN SEP 18 2016
.SHORT TERM...(This evening through Monday)
Issued at 424 PM EDT SUN SEP 18 2016
WV imagery and RAP analysis indicated a zonal pattern through the
nrn CONUS with a 130-140 knot 250-300 mb jet from the Pacific
Northwest into the nrn plains. A shortwave trough from srn Manitoba
into North Dakota, near the nose of the jet and associated WAA
supported only -shra/sprinkles over nrn MN.
Tonight, as the upstream shrtwv approaches expect increasing pcpn
chances from wrn Lake Superior into nw portions of Upper Michigan.
Since the stronger 700-300 mb qvector conv with the shrtwv and upper
level div with the left exit of the jet remains mainly to the north,
only chance pops were mentioned. With MUCAPE values into the 500-1000
J/Kg range and increasing effective shear values to 30- 35 knots,
some stronger TS may be possible with marginally severe hail.
Monday, the front will sweep through the cwa bringing gusty winds and
drier air to the area with gusts approaching advisory criteria of
near 40 knots over the higher favored terrain of the Keweenaw. With
the stronger 700-300 mb qvector conv and 900-700 mb fgen asociated
with the shrtwv shifting into the ern cwa, some sct/isold shra/tsra
may redevelop in the afternoon, mainly from KERY eastward. Sunshine
and mixing with 850 mb temps around 12C will support max readings in
the mid to upper 70s, warmest in downslope locations.
.LONG TERM...(Monday night through Sunday)
Issued at 346 PM EDT SUN SEP 18 2016
Monday night through Tuesday night: The cold front will continue to
slide off to the east of the U.P. Monday evening. On the back side
of the front, the Upper Great Lakes region will be placed between
broad low pressure over northern Ontario and high pressure building
in form the South, over the mid Mississippi Valley. This will keep
the U.P. under slight ridging at the surface through this time
period with nearly zonal flow aloft. Drier air will be in place,
keeping conditions fairly quiet with above normal high temperatures
and near normal overnight lows. For reference, normal highs this
time of year are around the mid 60s with normal lows in the mid 40s.
Wednesday through Thursday: As the aforementioned high pressure
system slides off to the east of the Upper Great Lakes, low pressure
will begin to organize over the Central Plains by Wednesday morning.
Behind the departing high and ahead of the approaching low pressure
system, moisture transport from the Gulf will increase as is evident
by the isobars being wide open to the moisture source coupled with a
decent pressure gradient. PWAT values rise are expected to increase
to around 1.5-2.0 inches by Wednesday night, which is about twice
climatology for this time of year. In addition to the increasing
moisture, a warm front is progged to lift northward toward the U.P.
late Wednesday afternoon and then become nearly stationary over the
area Thursday. Forcing will increase as the front approaches and
shortwave passes through the region Wednesday night. Isentropic
upglide will also increase on the WAA into the region with moisture
transport vectors perpendicular to the isobars on the 295-300K
isosurface. At the same time, the U.P. will be in the right entrance
region of a fairly strong upper level jet, again pointing toward
increased divergence aloft. All of this points to an increased
potential of heavy rainfall Wednesday night. Thursday the front will
still linger nearby, but the forcing/isentropic ascent will not be
quite as strong so the heavies rainfall may diminish; however, the
chances for showers and thunderstorms will continue through the day.
Thursday night through Friday: The front will continue to linger
nearby, probably just south of the U.P. through this time period.
Overall forcing does not appear to be too strong and there aren`t
any strong shortwaves progged to slide through during this time
period, but the chances of showers will continue due to the
proximity and weak forcing near the front. Exact details will be
ironed out for the exact placement of surface/upper-level features
as this time period gets closer, but it does look messier and wet
toward the end of the work week.
Saturday and Sunday: Significant model differences are still showing
up from model to model and run to run during this time period, which
gives little confidence in the timing and placement of the better
chances of showers and thundestorms, but it does appear as if the
upcoming weekend will be unsettle at times. At this point have
continued to lean toward the consensus of the longer term models.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 146 PM EDT SUN SEP 18 2016
Stratocu with cigs near MVFR threshold at CMX and SAW are expected
to give way to VFR conditions by mid to late afternoon as drier air
moves in from the west. The approach of a cold front will bring in
mid-level clouds and some isolated shra to the western taf sites by
late evening/overnight. VCSH was mentioned at IWD and CMX to cover
this. Also increasing SW winds ahead of the front will result in
LLWS overnight. Gusty west winds are expected to develop by mid
Monday morning behind the cold front, especially at CMX where gusts
above 30 knots are likely.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 424 PM EDT SUN SEP 18 2016
a tightening pres gradient between high pressure area over the
Plains and low pressure tracking through northern Manitoba toward
Hudson Bay will cause SW winds to increase as high as 25 knots late
tonight and to 30 knots on Monday as shift wsw in the wake of the
cold front associated with the Canadian low. In fact, there could be
a period of gale gusts to 35 knots between Isle Royale and the
Keweenaw Peninsula late Monday morning into the afternoon hours as
west-southwest winds will become enhanced by channeling between
these features. West winds should generally diminish to 25 knots Mon
night into Tue as gradient slackens with Canadian low lifting
farther ne across Hudson Bay. Winds will diminish to less than 20
kts Wednesday into Friday under weak pres gradient across the Upper
Lakes.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...JLB
LONG TERM...KEC
AVIATION...JLB
MARINE...JLB
Area Forecast Discussion
National Weather Service Morristown TN
255 PM EDT SUN SEP 18 2016
.SHORT TERM (This Afternoon through Monday)...
Widespread showers across the forecast area with a few embedded
rumbles of thunder. A cold front is located along the Cumberland
Plateau with N-NW winds across Middle TN. This boundary has slowed
over the last few hours as upper level winds have become more
parallel to the boundary. Current water vapor imagery and RAP upper
air analysis indicate a more robust upper level trough moving across
the Mid-Mississippi River valley. This wave will cause the front to
speed up later this evening and into the overnight hours. PW values
across the region remain elevated in the 1.8-2.1 inch range, which
is around the 99th percentile for mid-September. Based on the
current radar trends, continued with highs PoPs through the
remainder of the afternoon and evening with PoPs decreasing from
west to east later tonight. So far have seen around three quarters
of inch of precip. at Chattanooga with some locations potentially as
high as 2 inches. Due to the lack of rainfall over the last few
weeks, these values are well below 1hr and 3hr flash flood guidance
and do not expect any flooding issues. Patchy fog will be possible
tonight with plenty of low-level moisture hanging around the surface
boundary. Dewpoints will be up into the 60s with a few lingering
showers across SW VA and NE TN later tonight.
On Monday, dry conditions will return to the forecast area as the
cold front pushes to the east. Not seeing a sharp drop off in
dewpoints with values expected to remain in the low to mid 60s
tomorrow. The upper level trough will begin to cutoff across GA/SC
during the day tomorrow with higher heights building closer to
home. These higher heights and lack of any substantial cold air
advection behind the front will push high temperatures back up into
the 80s once again on Monday.
.LONG TERM (Monday Night through Sunday)...
Behind the front the upper level ridge will be the main driver of
the weather through most of the upcoming work week. With the sunny
skies and increasing pressure temperatures will rise above normal by
Monday, and they will likely remain above normal through the rest of
the 7 day forecast. Some decent moisture could return to the area
towards the end of the work week and allow for some diurnal showers
with the best chances likely occurring over the higher terrain. The
best rain chances for this portion of the forecast will likely come
as we move into the weekend and another frontal boundary makes its
way towards our area. Models are not in great agreement on
timing/strength of the low that moves across the northern portion of
the U.S. but at this time they do agree that widespread
showers/thunderstorms look to possible as it moves through.
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 68 88 65 91 / 20 10 10 0
Knoxville McGhee Tyson Airport, TN 64 86 64 87 / 30 10 10 0
Oak Ridge, TN 65 86 63 88 / 20 10 10 0
Tri Cities Airport, TN 64 83 60 85 / 60 10 10 10
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...None.
TN...None.
VA...None.
&&
$$
MA/ABM
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
114 PM EDT SUN SEP 18 2016
.SYNOPSIS...
17Z water vapor and H4 RAP analysis show that weak upper level
ridging is still in place over the eastern Gulf of Mexico and
Florida peninsula this afternoon. A little bit of influence from
this ridge can be seen in the 12Z KTBW sounding which showed a
subtle subsidence inversion around 700mb. Even above this
level...the column is not particularly dry...and the PW for the
layer is still above average at over 2.1". The ridge overhead will
slowly break down during the next 24-36 hours as a northern stream
trough/amplification currently over the MS valley digs into the
southeastern CONUS.
At the surface...FL peninsula continues to reside within a weak
pressure gradient between high pressure over the central/eastern
Gulf of Mexico...and TD Julia spinning of the Carolina/GA coasts.
As mentioned this gradient is very weak...and our lower level flow
will become increasingly dominated over the next several hours by
the east and west coast sea-breezes moving inland...along with
convective cold pool outflow. Temperatures early this afternoon as
rising through the 80s...with afternoon high temps expected within
a degree or two of 90. Once the sea-breeze becomes
established...the development of scattered storms will commence
near the coast. Nothing out of the ordinary expected later this
afternoon and evening with these storms...as they tend to migrate
inland with time and eventually congeal east of the I-75 corridor
during the early evening.
&&
.SHORT TERM (Tonight through Monday)...
Ensemble solutions from the hires explicit convection guidance
suggest storms linger over the interior until around 10-11 PM
where the east and west coast sea-breeze circulation have met...
and then quickly dissipate. Much of the overnight post midnight
looks dry over the landmass...with a few isolated showers
developing across the coastal waters late with the land breeze.
Low temperatures look similar to previous nights with lower to
middle 70s interior and middle to upper 70s along the immediate
coast.
A rather ill-defined low level pattern continues into the first
day of the work week. Generally quiet morning expected with some
patchy fog...and then temperatures warming through the 80s under a
developing sct cumulus field. 1000-700mb flow is shown by the GFS
to shift a bit...and become mostly light onshore as opposed to
previous days...and this should assist the inland propagation of
the west-coast sea-breeze during the afternoon hours. With this in
mind...would think the best window of opportunity for a storms
close to the coast will be during the early/mid afternoon...with
the majority of the scattered convection then moving to the
interior.
The main synoptic energy / QG forcing associated with the mid-
level trough digging into the southeast that we discussed in the
synopsis will be passing off to our north. However...the GFS/EC
do both show at least some weak swath of 500-300mb Qvector
convergence sliding over northern Florida Monday afternoon...along
with slightly cooler mid-level temps. Nothing here looks
dramatic...but perhaps just enough ingredients aloft to enhance a
few stronger updrafts along the inland propagating sea-breeze
over our northern zones...especially Levy/Citrus/Sumter counties.
High temperatures for Monday once again look to be in the mid/upper
80s at the coast...and right around 90 degrees inland.
&&
.MID/LONG TERM...
The mid and long term forecast periods feature more of the same
weather for west central and SW Florida as summer will continue its
grip on the peninsula. Tuesday, a weakening frontal boundary will be
draped across the Big Bend region. This front will bring with it
some slightly drier mid-level air helping to limit tstm activity
across northern zones but to the south, high-end scattered to
numerous tstms still expected.
On Wednesday, a mid-level cutoff low is expected to develop in the
vicinity of coastal Georgia while at the surface high pressure will
become established once again north of the region bringing us back
into a easterly flow regime through the weekend. Some drier air may
swing into portions of the area on the western edge of the mid-level
low helping to suppress tstm activity a bit but still expecting at
least scattered PoPs (30-50% coverage) for the area into next
weekend. Afternoon temperatures will continue within a degree or two
of 90 with low to mid 70s dewpoints making it feel closer to 100.
&&
.AVIATION...
Expect generally VFR conditions for all terminals with light
winds turning onshore near the coast. Scattered mid afternoon and
evening storms may briefly impact any of the terminals through
03Z...however greatest potential for a later evening storm after
00Z will be at KLAL.
&&
.MARINE...
A weak area of high pressure will remain in place over the eastern
Gulf of Mexico through the next couple of days. Winds and seas
will remain low with the proximity of the high pressure. Light
east or variable winds will become onshore near the coast each
afternoon. A few isolated showers or storms are possible each
overnight and early morning with locally higher winds...however
most of the thunderstorm activity through early in the week will
be over the landmass of the peninsula.
&&
.FIRE WEATHER...
A weak area of high pressure will hold over the Florida Peninsula
through the next couple of days. No significant weather or fire
weather concerns are anticipated...other than a scattering of many
late afternoon and evening thunderstorms. Relative humidity values
will remain well above critical levels. Some patchy late night fog
is possible for the usually fog prone areas...however no
significant areas of dense fog are expected the next several
nights.
&&
.Preliminary Point Temps/PoPs...
TPA 90 78 91 76 / 30 10 50 30
FMY 91 77 91 75 / 30 20 50 30
GIF 92 75 91 74 / 50 30 50 30
SRQ 91 77 91 76 / 20 10 50 30
BKV 90 74 91 73 / 30 10 50 20
SPG 91 79 90 78 / 20 10 50 30
&&
.TBW Watches/Warnings/Advisories...
FL...None.
Gulf waters...None.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...Mroczka
MID TERM/LONG TERM/DECISION SUPPORT...McKaughan