Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/12/17
Area Forecast Discussion
National Weather Service Albany NY
1045 PM EDT Tue Apr 11 2017
.SYNOPSIS...
A cold front will cross the region overnight, bringing a chance
of showers. Drier and much cooler weather will return for
tomorrow afternoon into Thursday with high pressure building
into the region. Fair weather is forecast for Friday after a
chilly start to the day.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
As of 1045 PM EDT...A prefrontal sfc trough moved through most
of the region, as the cold front continues to slowly move
south/southeast from western and northern NY, as well as north-
central VT. The shower activity has diminished over the region
based on the KENX radar. However, a weak wave and mid-level
short-wave is approaching from w-cntrl PA. This will increase
the shower coverage once again along the front, and we increased
the pops after midnight, especially between 1 and 3 am based on
the latest HRRR and NAM12. There is little or no instability so
the slight chc pops for thunderstorms were removed from the
forecast. Temps were retooled based on the hourly trends, as
temps are in the lower to mid 40s over the southern Adirondacks
and southern Greens and 50s to lower 60s, except over the mid-
Hudson Valley and NW CT, where some mid and upper 60s continues.
Lows tonight will be in the 40s to upper 50s.
Lingering isolated to scattered showers are expected in eastern
NY Wednesday morning and lasting into early afternoon in
western New England. Some clearing is possible by mid to late
afternoon with breezy/gusty west to northwest winds spreading
across the region behind the cold front. The boundary layer
thermal gradient tightens across our area as the cold front
tracks through, which could promote more cloud cover, which
could affect highs Wednesday. Still, any sun and the gusty winds
should aid in mixing and high temperatures in the lower to mid
60s but around 70 to lower 70s south and some 50s in northern
areas. That is potentially a big difference in temperatures form
north to south but the tight boundary layer thermal gradient
associated with the cold front will be right over us.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
Tight pressure gradient Wednesday night will lead to continued
breezy conditions. Cyclonic flow and residual moisture will lead
to some clouds and possible some snow showers over the southern
Adirondacks. Lows Wednesday night area expected to be in the
upper 20s to upper 30s. Thursday will be dry and breezy at
times. Highs should be a few degrees cooler than on Wednesday,
in the upper 40s to near 60. High pressure builds in for
Thursday night with mainly clear skies expected. Lows Thursday
night will be in the upper 20s to mid 30s, although if skies
remain mostly clear, all areas may drop to near or below
freezing.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
The period starts out on Friday with surface high pressure over the
region with a dry northwest flow aloft. This should result in a
tranquil day with near to slightly above normal temperatures.
The high will drift eastward off the southern New England coast
Friday night, but will remain in control of our weather
providing dry and cool conditions. Lows Friday night in the
30s.
Saturday should start out dry in eastern areas, but some showers
are possible during the morning west of the Hudson River. Chances
for showers will increase by afternoon from west to east as
isentropic lift increases ahead of a warm front approaching from
the west. Highest POPs are forecast over the southern
Adirondacks and western Mohawk valley, but all areas may see
some rain by sunset on Saturday. Highs saturday in the 50s and
60s.
At this time Sunday does not appear to be a washout, although we
will have to watch for potential showers and even some
thunderstorms, especially during the afternoon/evening. Models
indicating some instability developing in a general warm sector
ahead of a cold front pushing south from Canada. Models also
showing quite a bit of moisture in the warm sector. 850MB temps
rise to around +12C. Cloudiness will modulate temperatures so
areas that see sunshine could get quite warm. Latest guidance
indicating valley locations from Albany southward could reach
into the 70s before the cold front moves through Sunday night.
Mainly drier, cooler and breezy conditions expected for Monday in
wake of the cold front passage with gusty northwest winds and
perhaps a few mountain showers.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
A cold front will slowly move southeastward across eastern NY
and western New England tonight and through Wednesday morning. A
weak disturbance moving along the front will produce some
scattered showers. Drier weather will return in the wake of the
front tomorrow afternoon.
VFR conditions will be in place early this evening, but clouds
will thicken and lower between 05Z-09Z from KGFl southward to
KPOU with some showers moving in ahead of a cold front a weak
disturbance moving along it. Cigs/vsbys will lower to MVFR
levels especially between 08Z-12Z from KALB-KPSF northward with
perhaps some IFR CIGS at KSPF btwn 10Z-17Z. The showers may
reach KPOU by 12Z...and last until about 17Z. MVFR conditions
should improve to VFR levels with the showers ending btwn 15Z-
17Z at KALB/KGFL/KPOU. Some lingering MVFR cigs will persist
around 2 kft AGL at KPSF until about 20Z. Expect scattered to
broken stratocumulus and high level clouds in the late afternoon
in the wake of the front. The thunderstorm threat has
diminished and has not been included in the TAFS at this time.
The winds will back from the west to northwest at 5-10 kts to
the southwest to south at 4 to 7 kts between 05Z-08Z. The winds
will increase from the west to northwest at 10-15 kts in the
late morning into the afternoon with some gusts in the 20-25 kt
range at KALB/KPSF.
Outlook...
Wednesday Night to Thursday Night: No Operational Impact. NO
SIG WX.
Friday: Moderate Operational Impact. Chance of SHRA.
Friday Night: Moderate Operational Impact. Chance of SHRA.
Saturday: Moderate Operational Impact. Chance of SHRA...TSRA.
Saturday Night: Moderate Operational Impact. Chance of SHRA.
Sunday: Low Operational Impact. Breezy NO SIG WX.
&&
.FIRE WEATHER...
Gusty south to southwest winds to 20 mph expected this
afternoon into this evening with RH values around 30 percent...
A cold front will cross the region tonight, bringing a chance
for showers and thunderstorms. Drier and much cooler weather
will return for later Wednesday into Thursday with high pressure
building into the region. Fair weather is forecast for Friday
after a chilly start to the day.
Relative humidity values will recover to 80 to 100 percent
tonight night and drop to 50 to 70 percent on Wednesday. RH
only recovers to 60 to 80 percent on Wednesday night.
Winds will be west at 5 to 10 mph tonight and west at 10 to 20
mph on Wednesday. Winds will shift to the northwest Wednesday
night and continue at 10 to 20 mph.
&&
.HYDROLOGY...
Warmer temperatures today will result in increased runoff due
to snow melt. River levels will need to be monitored due to
snow melt for basins with significant snow pack such as in the
southern Adirondacks, upper Mohawk, upper Hudson and into
southern Vermont.
Scattered showers and thunderstorms this afternoon through
Wednesday will result in basin average rainfall of a quarter of
an inch or less but point rainfall totals could be up to a half
inch.
The following river point has a flood warning in effect:
Riverbank (Schroon River).
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/11/Wasula
NEAR TERM...11/Wasula
SHORT TERM...SND
LONG TERM...SND
AVIATION...Wasula
FIRE WEATHER...SND
HYDROLOGY...SND
Area Forecast Discussion
National Weather Service La Crosse WI
1100 PM CDT Tue Apr 11 2017
.SHORT TERM...(This evening through Wednesday night)
Issued at 300 PM CDT Tue Apr 11 2017
Clouds have been very slow to erode and move out today as surface
high pressure moves into the region. However, RAP low-level RH
fields suggest clouds should finally start to dissipate and move
from west to east late this afternoon/evening with all but the far
east clearing out by sunset. With light surface wind, clearing
skies, and moist low-levels, there is a chance for some patchy
fog tonight along and east of the MS River. However, the light
wind layer is rather shallow, so not expecting widespread
development.
Cloud cover increases rapidly Wednesday ahead of a fast moving
short-wave aloft. An elongated surface trough develops from CO to
central IA in response to this wave with a west-east oriented warm
front in the vicinity of I-80. Models suggest two main areas of
rain with this system late Monday afternoon and Monday night. The
first is associated with isentropic lift/mid-level frontogenetical
forcing across much of the forecast area. And the second is more
closely tied to the surface warm front along the nose of the best
850-700 hPa moisture advection. Instability is weak overall with
unfavorable low-mid level lapse rates, so any thunder should
remain south of the forecast area. Precipitable water values do
increase to around three quarters of an inch, resulting in rainfall
amounts from 0.25-0.75 inches with the highest amounts south of
I-90. Despite overcast skies, temperatures Wednesday will rise
back into the lower 60s within broad warm air advection regime.
.LONG TERM...(Thursday through Tuesday)
Issued at 300 PM CDT Tue Apr 11 2017
Thursday will remain mostly cloudy, but lingering rain showers are
expected to move out of the area through the day with 500 hPa
ridging aloft and surface high pressure nosing south from Canada.
Highs will top out in the mid 50s to lower 60s with light
easterly wind.
A broad trough moves into the intermountain west on Friday,
allowing a short-wave to race northward into the Upper Midwest
within southwest flow aloft. Still some timing differences between
medium-range models with the ECMWF 6-12 hours faster than the GFS.
However, general idea is for showers and thunderstorms to lift
northward through the day and into Friday night within broad warm
air advection regime. 0-3 km MUCAPE does increase up to 1000 J/kg
by 06Z Saturday, but overall shear is rather weak (generally less
than 30 kts), so not anticipating any severe storms at this time.
Temperatures Friday will be in the 60s.
Additional shower and thunderstorms are possible Saturday as a
secondary northern stream short-wave swings a cold front across
the forecast area. Instability and deep layer shear do increase
through the day, but model soundings suggest there may also be
capping issues. Too early to discern severe potential, but
something to watch through the week.
High pressure will dominate the regional weather pattern Sunday
into Monday, resulting in partly sunny skies and dry weather.
Temperatures will range from the mid 50s to mid 60s. Another
chance for precipitation then moves in on Tuesday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 1100 PM CDT Tue Apr 11 2017
Cigs: mostly skc/sct conditions through 12z, then increasing
high/mid level clouds from the west Wed morning - associated with an
approaching upper level shortwave trough. The cigs will continue to
lower through 00z, likely holding VFR though through the period. Wed
night should see a drop into MVFR/IFR, holding into Thu morning.
VSBY/WX: t/td spread only 7 F at 03z at klse, and light sfc/near sfc
winds through much of the night time hours, leads to some questions
on the potential for valley fog. HRRR/RAP/NAM12 bufkit soundings
hint at it for KLSE, but not enough to include in the forecast. Will
continue to monitor.
Otherwise, don`t expect any impacts til closer to 00z thu as the
upper level shortwave/warm air advection/west-east running
frontogenetic region results in areas of -shra for the region.
Expect a drop to MVFR for Wed night as the rain sets in.
Winds: generally light from the southeast, picking up and more
southerly Wed before a slight shift back southeast Wed night.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
SHORT TERM...Rogers
LONG TERM...Rogers
AVIATION...Rieck
Area Forecast Discussion
National Weather Service Cleveland OH
933 PM EDT Tue Apr 11 2017
.SYNOPSIS...
A cold front over the southeast counties will move off to the
southeast this evening the high pressure will push east across the
region late tonight into Thursday. A series of lows will move
northeast along a front over the upper midwest late Friday through
Sunday eventually pulling a cold front southeast across the area
Sunday.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Showers with the cold front continue to move east of the area at
this time. Colder air continues to move east into the area in
the wake of the cold front. Temperatures should continue to fall
through the night in the cold air advection. Latest satellite
imagery shows cloud shield advancing east and will be slow to
clear out from west to east overnight.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY NIGHT/...
The high will be shifting east across the cwa Wed into Thu and
should keep conditions dry, but cooler into Thu with highs on Wed
only from around 50 far ne to the lower 60s far sw. Lows Wed night
should range from the mid 30s east to the lower 40s west. Temps Thu
should moderate a few degrees warmer as winds veer to east to se to
no longer be coming off the chilly lake.
Moisture from the next system will be returning Thu, focused by a
warm front that lifts into the cwa. There is a small chance a shra
could occur in the north Thu into Thu night as an upper s/w drops
ese across the area providing enhanced forcing.
Lows Thu night will not be as cool as the previous few nights.
The next s/w should ride ne from the southern plains to be near NW
OH by 12z sat. The added energy from this upper system should bring
a batch of shra/tsra east into the cwa Fri night. Temps will
continue to trend warmer Fri and Fri night as the warm front lifts
further north.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
Warm front will lift across the region on Saturday with a chance of
thunderstorms near it. The region will then be in the warm sector at
some point Saturday afternoon into Sunday afternoon. So another
round of thunderstorms will be possible as a cold front moves west
to east across the region Sunday afternoon and evening. Cooler on
Monday in the wake of the cold front.
Saturday looks to be the warmest day of the long term with highs
well into the 70s for most locations. Cloud cover and developing
thunderstorms should limit the heating slightly on Sunday with highs
within a couple degrees of 70s. Cooler Monday with highs closer to
seasonal averages.
&&
.AVIATION /00Z Wednesday THROUGH Sunday/...
A bit of a quandary the next 12 hours or so as guidance
diverges. The cold front which has passed through all but KCAK
and KYNG will move southeast out of the area early this evening
with winds turning wnw behind the boundary. Conditions behind
the front will be VFR to start. Guidance then diverges with the
NAM leaning more toward MVFR CIGS developing through the night
vs mostly VFR with the GFS as high pressure builds in. High
resolution HRRR also supports VFR cigs. In short dont fully
trust that MVFR CIGS dont develop in the post cold front airmass
overnight. For now will allow for an MVFR CIGS for a couple
hours this evening northwest given proximity to the deck as MI.
Will then continue a low VFR cigs through the night. Will also
have an MVFR CIG around dawn KMFD. Further east low level
moisture actually pivots into the area affecting primarily KERI
after 08z. Will have and MVFR CIGS at in a tempo group to start
at KERI and again at 10-14z. For the balance of Tuesday am
expecting VFR.
OUTLOOK...Non-VFR possible Friday night into early Saturday.
Non-VFR possible in showers/thunderstorms on Sunday.
&&
.MARINE...
Cold front moving across the western basin of Lake Erie should clear
the east end of the lake by midnight. Westerly winds will become
more from the northwest toward sunrise. Waves may briefly touch 3 to
5 feet across the east end of the lake overnight but it will be
brief so we will hold of on a small craft advisory. High pressure
will then take control of the lake on Wednesday with light winds. As
the high shifts eastward and a warm front moves toward the lake
Thursday into Friday northeast to east winds will increase. This
flow may persist long enough to build waves across the western basin
for the end of the week.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...None.
&&
$$
SYNOPSIS...Adams
NEAR TERM...Lombardy
SHORT TERM...Adams
LONG TERM...Mullen
AVIATION...TK
MARINE...Mullen
Area Forecast Discussion
National Weather Service State College PA
1031 PM EDT Tue Apr 11 2017
.SYNOPSIS...
A cold will move across Pennsylvania this evening and overnight.
Dry and cooler conditions will follow for Wednesday through Friday
under a ridge of high pressure.
&&
.NEAR TERM /UNTIL 7 AM WEDNESDAY MORNING/...
Frontal analysis by WPC puts the front somewhere over the NW
counties, and drier with NW wind direction does appear there
now. The front should move slowly SE through the night. However,
the pressure pattern is warped by the current meso high
under/behind the current area of showers. Vort max is working
through the CWA and is just about over Happy Valley. The few CGs
associated with the TS right under it have all but died out.
The rain filled in nicely, but it is still pretty light.
HRRR/RAP play up a scenario where the focus for showers remains
along this same axis from IPT-JST - mainly to the NW of MDT and
SE of FIG - through much of the night before pivoting and
sliding closer to MDT. However, precip may never reach into
LNS. Will keep just a 20 POP there for the night, but keep them
high-ish between MDT and FIG. Convection in the OH valley is
still headed this way, but may not survive the trip across WV as
a cold outflow boundary has been pushing south from the earlier
convection and should contribute to an overall increase in
stability.
Prev...
Instability still trying to work up to the very high LFC, and
just a few showers have been going on thus far this evening.
However, a nice connection between some showers in the E and the
SW ahead of a decent short wave trough in srn OH is developing.
Will keep POPs in the high-chc very low likely range for the
central counties this evening. temps still very warm and RHs
still pretty low with 40s widespread. Thus, bases are very high
(for Central PA standards) and not a lot of precip has reached
the ground at this point. A nice rainbow out the window a few
mins ago was most likely a virga-bow with dbZs only in the m30s
in those showers over Mifflin Co.
Prev...
As of mid day the cold front extended from a low over southern
Ontario down through central Ohio. The leading edge of showers
was trekking through the Northern Mountains. Latest lightning
data shows that the thunderstorms have moved into NY. But the
atmosphere remains marginally unstable with mid level lapse
rates exceeding 7C/KM covering most of PA and a few hundred
joules of CAPE being analyzed depending on what the near term
model of choice is.
Models show a narrow ribbon of enhanced moisture pooling up
ahead of the approaching front helping support some modest
destabilization. Local dewpoints in the 40s will climb into the
u40s and mid 50s in advance of a cold front later today across
the western half of the state, and continue across the remainder
of the region this evening and overnight.
SPC has confined the Day 1 Marginal Risk to north of the NY/PA
border, closer to the nose of the upper jet. Most of PA is
forecast to remain under the relatively unfavorable right front
exit of this jet.
Latest HRRR kills most of the shower/thunderstorm activity as it
moves into central PA toward nightfall, before bringing a new
surge of showers up over the forecast area during the late
evening into the wee hours of Wednesday. While forecast surface
based LI`s suggest the boundary layer stabilizes as the sun
goes down, mid level lapse rates are forecast to be relatively
steep, exceeding 6C/KM along the front as it slides across later
tonight. So a nocturnal thunderstorm cannot be ruled out with
the passage of the front.
Highs today are generally overachieving in the sunny wedge east
of the cloud mass covering the NWRN 1/2 or so of my CWA. I
nudged things a tad higher than the blended MOS yielding 80 or
above for much of the eastern portion of my forecast area.
It will remain mild overnight with lows some 10-20 deg above
normal.
&&
.SHORT TERM /7 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
Models agree that the cold front will either be just leaving far
SERN Lancaster county around sun rise Wednesday or will already
be east of the area. The last of some lingering rain showers
will be similarly exiting the region leaving the bulk of
Wednesday dry with brightening skies.
All model guidance concurs on a nice, but moderately cooler
Wednesday. Highs in the 50s to around 70 will still average
several degrees warmer than normal.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
Model and ensemble guidance are in pretty good agreement on the
overall pattern and sensible weather impacts through the period.
Seasonal temperatures through the end of the week will trend
warmer over the weekend, likely reaching a pre-frontal maximum
on Easter Sunday before cooling off modestly into early next
week. Dry conditions are expected through Friday with an
increasing risk for rain showers over the weekend before the
area drys out again next Monday/Tuesday.
In terms of fcst details, there is not much to target/highlight.
Shortwave energy embedded within a low amplitude trough exiting
the Northeast U.S. streaks through the Upper OH Valley and
Northern Mid Atlantic later Thursday into Friday while a frontal
boundary sets up from the Mid MS Valley eastward through the
Delmarva. Some pcpn may focus along the frontal zone but high
pressure should keep it confined to the south/west of PA. The
boundary then pivots northward as a warm front on Saturday as
an upper ridge builds over the Southeastern U.S. It appears the
main focus for showers and perhaps a few thunderstorms is with
a cold FROPA on Sunday. Hedged Sunday max temps above NBM/ECENS
blend with a mild SW flow ahead of the approaching cold front.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
A weak cold front is now nudging into far Northwest Pennsylvania
this evening at 00z. Weak but discrete band of showers just to
the east of Erie seems to depict the front and wind shift line
well.
Area of light showers, and at 00z one isolated thunderstorm near
Somerset, in advance of the front. HRRR has consistently been
handling precipitation well this evening. This model depicts
the area of showers to hang in across the Central Mountains
through about 07z, before weakening later in the overnight. HRRR
also not producing much precipitation with the actual front,
but continues to hint that scattered showers will accompany
FROPA overnight.
Lower ceilings have begun to break out across the Western
Mountains, and this trend will continue post-frontal as winds
shift to the west-northwest. Moisture from the pre-frontal
showers, combined with upslope flow, will bring IFR conditions
to KBFD and KJST overnight...with some guidance suggesting a
period of LIFR ceilings.
Over central airfields, expect some MVFR conditions with the
showers and frontal passage overnight. Areas in the southeast
will likely remain VFR with just a passing shower after 06z.
Clearing trend begins mid Wednesday morning, with all airfields
back to VFR by early afternoon.
As previous TAFs indicated, have not included thunder, with low
likelihood and coverage. Will have to watch KJST/KAOO though,
following radar persistence for the lone TSRA cell.
VFR conditions for the entire region by late morning/early
afternoon through the end of the week.
Outlook...
Thu-Fri...No sig wx expected.
Sat-Sun...Sct showers. Restrictions poss NW.
&&
.CLIMATE...
A daily record high temperature of 86 degrees has been set today at
Williamsport. This breaks the old record of 82 degrees set in
1922.
A daily record high temperature of 86 degrees has been set today at
Harrisburg. This breaks the old record of 84 degrees set in
2011.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...La Corte
NEAR TERM...Dangelo/La Corte
SHORT TERM...La Corte
LONG TERM...Steinbugl
AVIATION...Jung
CLIMATE...
Area Forecast Discussion
National Weather Service Duluth MN
942 PM CDT Tue Apr 11 2017
.UPDATE...
Issued at 942 PM CDT Tue Apr 11 2017
Skies have cleared across the Northland this evening. We lowered
temperatures a bit in spots and increased them late in the
Brainerd Lakes/Leech Lake area. There were some showers moving
through eastern North Dakota and there is some concern they could
hold together and affect our western CWA after 08Z. The latest NAM
does bring some QPF into our southwest area and the HRRR also
shows some showers late. However, the airmass ahead of these
showers is quite dry and the leading edge of the precipitation was
diminishing some. Several of the other models show the
precipitation remaining west of our area. We did increase cloud
cover a bit but left the mention of precipitation out for now. A
light mix would be possible depending on how quickly surface
temperatures respond to the increase in clouds.
UPDATE Issued at 623 PM CDT Tue Apr 11 2017
Please see the 00Z Aviation Discussion below.
&&
.SHORT TERM...(This evening through Wednesday)
Issued at 332 PM CDT Tue Apr 11 2017
The upper level weather map features a broad low pressure trough
over southeastern Quebec and into the MN Arrowhead while another
shortwave trough was enter North dakota late this afternoon. The
eastern trough will gradually pull away tonight and as it does
surface high pressure will build into the region and help scour
out the clouds that have been linger over northwestern Wisconsin.
With the high over the region and very light winds, temperatures
will drop quickly after sunset. Lows in the teens could be seen
again in the Arrowhead while 20s elsewhere. Some dewpoints in the
Arrowhead have been in the single digits this afternoon, so will
need to watch and maybe lower forecast minimums. But, an increase
in clouds from the Dakotas shortwave could keep temperatures from
following too fast.
On Wednesday the surface high will move east out of Wisconsin. A
return flow from the south will help boost temperatures into the
50s. Another shortwave that will be moving across South Dakota and
across southern Minnesota will spread could northward Wednesday
afternoon with just a slight chance of showers over our extreme
southern portions of the forecast area.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 332 PM CDT Tue Apr 11 2017
The models are in good agreement concerning an upper level shortwave
that will slide across southern Minnesota and into central Wisconsin
Wednesday night and early Thursday. This shortwave will bring a
chance of light rain to southern portions of the Northland,
especially along our southern border. As the shortwave moves off to
the east, upper level heights will build considerably to the west.
This should provide dry weather for Thursday afternoon and evening,
before an upper level shortwave in southwest flow pushes quickly
into the Upper Midwest and western Great Lakes. Showers and
thunderstorms should push northward on Friday, with showers and
thunderstorms continuing Friday night and Saturday. The best chance
for thunder will be in the southern and southeastern portions of the
CWA, but will be possible just about anywhere due to the strength of
the upper level shortwave and rapidly decreasing stability. An upper
level trough will then settle into the region Saturday night and
Sunday, bringing cooler and unsettled weather for the remainder of
the weekend and into early next week. Temperatures will cool
considerably over the weekend and into early in the week, especially
at night, with some snow possible. Another strong system is expected
to move into the Northland Monday night and Tuesday, with another
high chance of precipitation across the region. The models are
actually in good agreement considering it is a week out.
Temperatures will climb into the 60s by Saturday, and then cool
considerably to the 40s to low 50s for highs by Monday and
Tuesday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 623 PM CDT Tue Apr 11 2017
VFR through the upcoming TAF cycle. High pressure will build
across southern MN/WI tonight into Wednesday, before sliding into
the Central Great Lakes. Behind the high, a shortwave trough will
dig into the Northern Plains. This will gradually spread light
near KHYR/KBRD by the end of the TAF period. Winds will remain
less than 10 knots through the forecast per the NAM/DLHWRF and
latest MOS guidance.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 27 56 37 56 / 0 10 10 10
INL 22 59 32 62 / 0 10 0 0
BRD 32 60 38 62 / 10 20 10 0
HYR 25 57 38 59 / 0 10 30 10
ASX 25 57 35 56 / 0 10 20 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&
$$
UPDATE...Melde
SHORT TERM...CLC
LONG TERM...DAP
AVIATION...WL
Area Forecast Discussion
National Weather Service Jacksonville FL
858 PM EDT Tue Apr 11 2017
.UPDATE...
Not much change to the forecast as weak high pressure ridging
remaining north of the region with an easterly steering flow
across NE FL/SE GA. Evening JAX sounding shows PWAT up just
slightly to 0.72", so atmosphere has just slightly more moisture
but despite this, still do not expect much in the way of shower
activity, at most a few sprinkles across the Atlc Coastal Waters,
and just a slight chance of patchy fog over inland areas of SE GA
and North FL along the I-10 corridor with the SREF showing 20%
chances of FOG and HRRR showing a few spots of 1-5 mile fog
possible just inland from the JAX-BQK corridor but still not
likely significant enough to include in the forecast. Expect lows
in the 50s inland and near 60 along the coast. Expect another day
of partly sunny skies in the morning on Wednesday as fair weather
cumulus develops in the easterly flow then advances inland as the
Atlc Coast sea breeze marches inland with sustained winds of 10-15
mph and temporary gusts to 20-25 mph at times. Highs remain
similar to today with Max temps in the mid/upper 70s along the
coast and lower/middle 80s well inland.
&&
.AVIATION...
Still mainly VFR through the next 24 hours. Low chances for MVFR
fog at inland TAF sites, and have placed TEMPO 5SM at KVQQ.
Otherwise some possible SCT clouds around 2500 ft still possible
to push into the coastal TAF sites towards morning, then as
heating begins during the morning hours some BKN CIGS around 3500
ft possible at TAF sites until mixing and sea breeze scatters out
the clouds around 4000 ft after 18z.
&&
.MARINE...
No changes with East flow generally in the 10-15 knot range and
seas 2-4 ft, although some slightly higher winds/seas possible in
the NE FL offshore waters.
Rip Currents: Moderate risk in the onshore flow.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 55 82 55 82 / 0 0 0 0
SSI 62 74 62 76 / 0 0 0 0
JAX 56 79 57 78 / 0 0 0 10
SGJ 61 77 62 76 / 0 20 0 10
GNV 55 81 54 81 / 0 0 0 0
OCF 55 83 56 82 / 0 0 0 0
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&
$$
Hess/Nelson/McGinnis
Area Forecast Discussion...UPDATED
National Weather Service Memphis TN
934 PM CDT Tue Apr 11 2017
.UPDATE...
Isolated/scattered areas of light rain showers will continue east
of the MS River into the early overnight. Latest rapid update
models appeared to have a good handle on rain.
GOES IR imagery showed clouds clearing to the west of the MS
River. HRRR suggests patchy fog likely overnight over the MS
delta southwest of Memphis. SREF is in general agreement, while
maintaining a 50 percent probability of < 1 mile surface
visibility further north, near the I-40 corridor. Will continue a
mention of patchy overnight fog in these areas.
PWB
&&
.PREV DISCUSSION... /issued 700 PM CDT Tue Apr 11 2017/
UPDATE...
Updated to include 00Z aviation discussion below.
PREV DISCUSSION... /issued 330 PM CDT Tue Apr 11 2017/
DISCUSSION...
The cold front continues to move slowly through the Mid-South this
afternoon. Winds are from the north and northwest across most of
the area, but tightest moisture gradient roughly mirrors the I-40
corridor. Showers have increased in coverage over the past few
hours, becoming a bit more organized and producing a few lightning
strikes over west TN in recent volume scans. The potential for
strong storms will remain low this afternoon given the muted
instability and weak vertical shear. Temperatures don`t look to
warm much more this afternoon and will likely cool a bit in areas
experiencing rainfall.
Showers will continue through the evening hours, waning overnight
as the front continues south and the shortwave trough moves east.
Farther north, patchy fog will be possible in areas where skies
are able to clear. Expect overnight lows generally in the 50s.
Generally dry conditions are anticipated on Wednesday and
Thursday, but a few diurnal showers and thunderstorms will be
possible across portions of north MS. Coverage should remain
limited should any convection develop. Afternoon highs tomorrow
will be in the upper 70s and lower 80s, with most of the Mid-South
reaching the 80s on Thursday. Low temperatures will generally
range from the mid 50s to lower 60s.
The Mid-South will remain under at least some influence of a low-
amplitude mid-level ridge through the weekend. As one wave lifts
northeast over this ridge on Friday, a few showers and
thunderstorms will be possible. Again, coverage should be limited
and most areas will remain dry. Generally dry conditions are
anticipated on Saturday, but rain chances return to the area
Saturday night and Sunday as a cold front moves south into the
region. Most of the dynamics will be well removed to the north of
the CWA and vertical shear will be weak. Thus, organized severe
weather is not anticipated. Rain chances continue area wide early
next week as this front stalls beneath quasi-zonal flow aloft.
High temperatures over the weekend will range from the mid 70s to
mid 80s with overnight lows in the upper 50s and lower 60s.
Johnson
&&
.AVIATION...
00Z TAF Set
An broken line of slow moving showers behind a frontal zone will
affect MEM...MKL...and TUP in the short term. For now all sites
are VFR, with the exception of MKL where MVFR ceilings exist.
Short term models indicate this band of rain exiting all sites
after 12/07Z or so, with heavy rain possible at MKL. If skies
clear behind this line of showers, MVFR and IFR conds will be
possible at all sites due to fog and low stratus around midnight
or so.
At this time, confidence remains about 60% that a low stratus
deck, IFR deck, will materialize at MEM after 12/06Z for which a
tempo group was added. All sites will return to VFR by late
morning as surface high pressure builds in from the west.
AC3
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
Area Forecast Discussion
National Weather Service Miami FL
815 PM EDT Tue Apr 11 2017
.AVIATION...Lull in SHRA activity currently, with chances
increasing along east coast 07Z-09Z as moisture surge moves in
from Bahamas. VCSH for all east coast sites after this time
through TAF cycle, though activity may shift a little more inland
after 18Z. Gustiness diminishes after 01Z, though east coast sites
remain 10-12kts through the night, becoming 15G22kts after 13Z-
14Z. Unsure if Gulf breeze will reach KAPF tomorrow, but trending
to site becoming WNW after 19Z. Additional SHRA vicinity KAPF
after this time with seabreeze convergence.
&&
.UPDATE...
Latest IR satellite imagery shows a distinct surge of moisture
moving from east to west across the Bahamas. This feature will be
our main player for our weather during the next 24-hours.
Clockwise flow from surface high pressure to the north will drive
this moisture towards southern Florida, approaching the coast by
Wednesday morning. The HRRR and Hi-Res WRF indicate increasing
chances of precip starting by around sunrise along the east coast
metro region. Have adjusted PoPs accordingly. Tomorrow afternoon,
forecast GFS SB CAPE values are between 500-700 J/KG and LIs
around -2C. Although a few strikes of lightning can not be ruled
out, confidence is too low to add to the grids on this update.
Otherwise, breezy easterly winds will continue overnight, mainly
along the Atlantic coastline. Smoke from the Cowbell fire may
cause periods of low visibility along portions of I-75 in interior
Collier County.
&&
.PREV DISCUSSION... /issued 428 PM EDT Tue Apr 11 2017/
DISCUSSION...
Through tonight: Latest water vapor imagery shows troughing along
the central CONUS with upper level ridging stretching from the
eastern Gulf to the western Atlantic. South Florida continues to
reside on the southern side of an elongated surface ridge to the
north. Clockwise flow around this feature brought easterly winds
to South Florida this afternoon, mainly in the 10 to 20 mph range.
Low level moisture advecting westward from the Atlantic will
generate light showers along portions of the eastern peninsula
this evening. However, as the air moves across the landmass, it
becomes much drier. Min RH values this afternoon ranged from
generally 50 to 60 percent along the east coast metro down to 30
to 40 percent over portions of Collier, Hendry, and Glades
counties. Thus, to account for this trend, a Red Flag Warning was
issued for these locations. The coolest weather has occurred
along the east coast metro, where onshore flow only allowed max
temperatures to top out in the upper 70s/lower 80s. Further west,
max temperatures have been higher, in the mid 80s, as it typical
for an easterly flow pattern. Tonight, persistent moisture
advection from the Atlantic will keep temperatures from falling
much below 70 degrees along the east coast metro. Minimum
temperatures may lower to the upper 50s to lower 60s across the
interior and Gulf coast, where drier air and better radiational
cooling will occur.
Tomorrow through Thursday: Surface high pressure will remain in
control over the Western Atlantic the next several days,
continuing the easterly flow pattern across South Florida. Both
the GFS and ECMWF push a surge of lower level moisture, currently
located near the Bahamas, over our region Wednesday morning
through Wednesday night. This increase in moisture, along with
diurnal heating should trigger scattered showers across the entire
CWA, with highest probability over the east coast metro and
interior regions. Forecast CAPE and other instability factors are
minimal, so not expecting any convection to develop. By Thursday,
models push the moisture to the the southwest over the Gulf, once
again decreasing shower activity over southern Florida. Maximum
Wednesday and Thursday afternoon are forecast to range from the
upper 70s/low 80s along the east coast metro to mid 80s across the
western interior, which is near normal for this time of year.
Friday through this weekend: Stronger high pressure to the north
will allow surface pressure gradients to tighten, bringing an
increase to the easterly flow...especially on Saturday.
Otherwise, status quo with temperatures near normal and scattered
light showers, mainly at night along the east coast metro.
MARINE...Moderate to fresh easterly winds will continue
throughout the forecast period as a ridge of high pressure remains
in place north of the area. Speeds will generally 15-20 knots
with seas 4-6 feet, sufficient for small craft to exercise
caution. Seas may increase to 6 to 7 feet along the Gulf Stream by
Wednesday afternoon. Easterly winds will increase near Small
Craft conditions early this weekend.
BEACH FORECAST...Moderate and occasionally gusty easterly breezes
will continue, keeping the rip current risk level high through
this evening. Moderate to strong rip currents will likely occur
through the rest of this week as easterly flow persists.
FIRE WEATHER...Surface high pressure to the north of the region
will lead to persistent easterly winds across south Florida over
the next several days. Expect very good to excellent dispersion
most afternoons. Isolated light showers will develop along the
east coast metro region with drier conditions further west. There
will be a increase in clouds and showers tomorrow and Friday.
Latest forecast trends show a slight increase in RH tomorrow, with
min RH values ranging from 45 to 55 percent in the western
interior. The Red Flag Warning over Glades, Hendry, and interior
Collier counties is set to expire at 8pm this evening. &&
.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach 70 79 69 79 / 20 40 30 20
Fort Lauderdale 71 80 70 79 / 30 40 30 20
Miami 70 81 69 80 / 30 40 30 20
Naples 64 82 64 83 / 10 30 20 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...Red Flag Warning until 8 PM EDT this evening for FLZ063-066-070.
High Rip Current Risk until 8 PM EDT this evening for FLZ168-172-
173.
AM...None.
GM...None.
&&
UPDATE...27/JT
AVIATION...88/ALM
DISCUSSON...27/JT
MARINE...27/JT
BEACH FORECAST...27/JT
FIRE WEATHER...27/JT
Area Forecast Discussion
National Weather Service Norman OK
830 PM CDT Tue Apr 11 2017
.UPDATE...
Low level moisture will make a return north overnight. This will
likely lead to stratus deck overspreading the area and the
possibility of patchy fog. Therefore have added some fog to the
forecast late tonight into the first part of the morning across
much of the area. Otherwise, only very minor tweaks to going
forecast.
30
&&
.PREV DISCUSSION... /issued 643 PM CDT Tue Apr 11 2017/
AVIATION...
VFR conditions are expected through about 8-9z with a
light/moderate east to southeast wind.
IFR conditions may develop at most TAF sites during the late
overnight into early Wednesday morning as moisture returns. A
recent run of the HRRR lowers visibility below 1/2 mile across
part of western north Texas and a large part of western Oklahoma
between 11-13z. For now, will reduce visibility to around 2 miles
with ceilings around 500-700 feet.
Ceilings and visibility should improve to at least MVFR conditions
by 16z.
PREV DISCUSSION... /issued 350 PM CDT Tue Apr 11 2017/
DISCUSSION...
Primary forecast focus is on increasing rainfall chances Wednesday
evening through Thursday, beginning across western north Texas into
western Oklahoma.
Anyone else in Oklahoma or western north Texas feeling the "patio
vibes" today? Seriously, it`s in the upper 60s and low 70s with a
light wind, the "get outside" advisory is in effect through the
evening.
Overnight, low clouds will gradually increase in coverage across the
region, from the Red River to the north. Looking at various Bufr
profiles, not quite sold on fog development across southern Oklahoma
and western north Texas, given boundary layer winds and dew points,
I am inclined to lean toward stratus developing across the region
late tonight, lingering through Wednesday morning. This will impact
low temperatures overnight, depending on when clouds develop and the
impacts of any insolation. Tried to highlight this with morning
lows, keeping them a tad warmer across the southern half of Oklahoma
into north Texas.
Through Wednesday, brief 500mb ridging will give way to the approach
of an open, yet defined, short wave trough lifting east/northeast
off the high plains of New Mexico and the Llano Estacado. You can
make out this feature on all three GOES-16 water vapor channels,
it`s currently pushing ashore on the Baja Peninsula and southern over southeast
Oklahoma and TeCalifornia. Ahead of this trough, low level
moisture will continue to pool across west Texas into the Texas
Panhandle and southwestern/western Oklahoma. A fairly broad area
of isentropic ascent will reside within this same sector,
providing the focus for developing scattered to numerous showers
and thunderstorms.
Convection, Wednesday, will likely be ongoing by midday across the
higher terrain of New Mexico, across the Sangre de Cristos and south
along the Sandias. This activity will gradually build eastward
through the day, across the Caprock Canyonlands and interact with
developing activity within the warm sector across western north
Texas and finally western Oklahoma into the evening hours. There is
a marginal risk for a few strong to severe storms in far western
Oklahoma, due to modestly steep mid-level lapse rates and modest
CAPE and shear, so a few hailers cannot be ruled out.
Overall, moderate to heavy rainfall is what can be expected, with over southeast
Oklahoma and Teamounts building steadily overnight through
Thursday. The heaviest amounts are expected between 1.50 to 2.25
inches, with some isolated areas getting closer to 3 inches. The
area affected will be portions of western north Texas, into
southwest and western Oklahoma into north central Oklahoma.
Flooding and flash flooding potential is fairly low, as rainfall
will be spread over several hours, for most of Thursday. However,
initial development and any training of storms could result in
some marginal flooding concerns, especially across western north
Texas into southwestern Oklahoma.
Rain chances will end through Friday, with lingering showers and
thunder through the morning across northern Oklahoma. Rain chances
will return over the weekend, Saturday evening through Sunday as a over southeast
Oklahoma and Tecold front moves into the region from the north.
Kurtz
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 51 75 59 73 / 0 10 50 50
Hobart OK 47 73 59 71 / 0 20 70 70
Wichita Falls TX 52 77 60 76 / 0 20 50 40
Gage OK 48 71 56 69 / 0 40 70 70
Ponca City OK 49 76 59 73 / 0 0 30 60
Durant OK 59 77 60 78 / 0 10 10 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...None.
TX...None.
&&
$$
30/06
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
745 PM EDT Tue Apr 11 2017
.UPDATE...
00Z water vapor and H4 RAP analysis shows a benign weather
pattern in place over the Florida peninsula...and this
pattern will be our weather through the middle of the week.
Weak amplitude ridging extends aloft from the
central/eastern Gulf of Mexico...over the state of Florida
and has provided the large scale suppression today to keep
our cumulus fields shallow and suppressed...and generally
prevented any shower activity within our forecast area.
These dry conditions will continue through the overnight
hours into Wednesday morning. BKN clouds along the coast
from Tampa Bay southward are a result of the broad speed
convergence at the coast with the sea-breeze that tried to
come inland today...but generally stalled near the beaches.
As diurnal heating decreases from here forward...this low
level convergence zone will weaken as well...and should see
this cloudcover break up and/or move slowly out to sea with
the prevailing synoptic easterly flow.
As we head through the daylight hours of Wednesday...the
upper ridge will begin to break down as shortwave energy
evolves slowly eastward along the northern Gulf Coast. While
this energy will not directly impact our region
Wednesday...the loss of strong suppression aloft will
produce an environment a bit more condusive to brief
afternoon pop-up showers. The environmental flow looks to
again prevent much inland penetration of the sea-breeze, but
most of the hires guidance members are showing at least a
speed convergence zone developing along the coast after 18Z.
This zone will likely host a few showers as we head deeper
into the afternoon. Rain chances are going to stay low
20-30%...and anything that does form will not be a drought-
buster. Still...a few of you might need to briefly turn on
the windshield wipers during the commute home tomorrow
evening from the I-4 corridor southward.
&&
.AVIATION (12/00Z through 13/00Z)...
No significant aviation concerns anticipated though the TAF
period. VFR conditions forecast to prevail through the
overnight/morning hours of Wednesday. Low level winds appear
steady enough to potentially prevent sea-breeze from making
inland penetration more than a couple miles on
Wednesday...and therefore keep winds at all terminals either
east or northeast. A sprinkle/shower possible along the
I-75 corridor after 20Z Wednesday, but any rainfall will be
light and brief. Low potential for precip will keep mention
out of current TAF package.
&&
.Prev Discussion... /issued 255 PM EDT Tue Apr 11 2017/
SHORT TERM (Tonight - Wednesday)...
Upper level ridging from the Gulf extending northeast across
Florida and up along the eastern seaboard will remain in
place through Wednesday, but will weaken some on Wednesday
as a short wave trough moving across the southeastern states
impinges upon it. At the surface high pressure offshore the
mid Atlantic coast will remain in place through the period
with an easterly wind flow continuing across the entire
forecast area. A dry subsident air mass will keep rain out
of the forecast tonight, however on Wednesday less
suppression from the upper ridge combined with enough low
level moisture may support some low-topped showers within
the easterly flow across central interior and across
southwest Florida during the afternoon where the best
moisture will reside and have included a low pop mention (20
percent) in these areas, otherwise dry weather will
continue. Temperatures tonight will run near seasonal norms
with lows in the upper 50s to lower 60s. Highs on Wednesday
with continue to run a few degrees above normal with highs
climbing to around 80 to the lower 80s along the coast, and
mid 80s inland.
LONG TERM (Wednesday Night - Tuesday)...
An upper trough will be moving over the state Wednesday
night and Thursday as a surface cold front stalls and
dissipates to the north of the state. High pressure and
upper ridging will then build over the region and remain
through Tuesday. Winds will generally be from the
east/northeast through the period, with some evening surges
possible. Conditions will remain mostly dry through the
period, with just an isolated rain chance Thursday afternoon
and then again for Tuesday afternoon. Temperatures will be
above normal through the period.
MARINE...
Surface high pressure offshore the mid Atlantic coast of
late will get reinforced by another ridge of high pressure
moving offshore the northeastern states late in the week
and during the upcoming weekend. The high will maintain an
elevated easterly wind flow (10 to 15 knots near shore and
around 15 knots offshore) over the Gulf waters through the
period with cautionary wind surges (in the 15 to 20 knot
range) likely over the offshore waters during the evening
and overnight time frames.
FIRE WEATHER...
Sufficient low level moisture will keep humidity values above
critical levels through the end of the week, so despite some
high ERC values in some locations Red Flag conditions are not
expected through the period.
&&
.Preliminary Point Temps/PoPs...
TPA 64 82 65 82 / 0 10 10 10
FMY 63 83 65 84 / 10 20 10 20
GIF 62 82 63 82 / 0 10 10 10
SRQ 62 81 64 83 / 0 10 10 10
BKV 58 83 59 82 / 0 10 0 10
SPG 66 80 67 82 / 0 10 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...None.
Gulf waters...None.
&&
$$
UPDATE/AVIATION...Mroczka
Previous Discussion...McMichael/Hubbard