Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/12/25
Area Forecast Discussion
National Weather Service La Crosse WI
1052 PM CDT Fri Apr 11 2025
.KEY MESSAGES...
- Warm up expected for this weekend with highs reaching into the 60s.
Some locations may reach into the 70s with a 40-80% chance of
highs at or above 70 degrees, mainly across Northeastern Iowa
and the river valleys of Wisconsin.
- Shower chances (30-60%) return for Sunday into Monday
- Windy conditions possible for Monday with medium-high
probabilities (50-80%) for wind gusts greater than 40 mph on
Monday afternoon.
&&
.DISCUSSION...
Issued at 221 PM CDT Fri Apr 11 2025
Warm Up into Sunday
Weak upper level ridging is expected to prevail through the
weekend as a surface high gradually drifts east across the area.
This will keep us dry through Saturday with temperatures
expected to warm into the 60s, and maybe even 70s by Sunday.
Warm air advection will begin to ramp up tomorrow as a surface
low begins to develop across the northern Rockies. The NBM
continues to show decently high probabilities (40-80%) of highs
climbing into the 70s for some locations on Sunday with the
continued WAA. This would largely be confined to areas across
Northeastern Iowa and notorious warmer spots in the river
valleys of Wisconsin. The only wrench in these possibilities
will be the abundance of cloud cover overhead and potential for
showers. Any rain would likely limit high temperatures in the
60s so have kept highs in the 60s for locations that have a
higher potential to see rain on Sunday.
Next System Sunday into Monday to Bring Showers and Cooler
Temperatures
An upper level shortwave trough will take shape across the Pacific
Northwest and continue to trek east through this weekend towards the
Upper Midwest. Ahead of this trough, the aforementioned surface low
will begin to take shape. As this begins to move east towards our
local area late Saturday into Sunday, increasing moisture from the
WAA will combine with lift ahead of the trough to create some
chances for showers, especially during the midday Sunday timeframe.
There remains good consensus between GFS and EC ensemble members
that areas along and north of I-90 should see measurable
precipitation but there remains differences in timing and
magnitude. The GFS starts to bring precip in early on Sunday
(before 12Z) with the surface low ejecting out of the Plains a
bit earlier. The EC ensembles hold the main batch of
precipitation off until later in the day on Sunday and into
early Monday. The GFS/NAM soundings show pWats around 1 inch
during the day on Sunday, indicating some fairly deep moisture
across the area. This is generally leading to higher QPF totals
from the GFS ensemble with more efficient rainfall seemingly
expected. Right now, QPF does not look terribly impressive with
the 11.13Z NBM showing probabilities of precipitation greater
than or equal to .10 of an inch around 20-40% for areas along
and north of I-90. Probabilities drop off further for
precipitation greater than or equal to .25 of an inch with less
than 20% for areas north of I-94.
Looking at the potential for thunderstorms during the day on Sunday
with some elevated instability present in 11.15Z RAP soundings
at LSE and OVS. Being elevated in nature, this would limit any
severe threat but there is a chance if the slower guidance of
the EC comes more to fruition, this could lead to more
widespread destabilization across the Upper Mississippi Valley
and allow for some surface based convection. There is low
confidence in this happening as of right now due to the mid-
range model differences in timing of the trough/surface low, but
this is something that will need to be monitored going forward.
Right now joint probabilities of MUCAPE greater than 500 J/kg
and bulk shear greater than 30 kts from the grand ensemble
(GEFS/EC/Canadian) remain less than 15% across portions of our
area for Sunday.
The cold front is expected to move through the area late Sunday into
early Monday which should generally bring rain chances to an end
across the bulk of our area. Winds behind the front will shift to
the northwest, bringing cooler Canadian air with it. High temperatures
Monday will range from the upper 40s to the upper 50s, a slight
increase from the previous run of the NBM. As the surface low
exits to the north and east Monday, the pressure gradient will
tighten on the back side of the system, bringing gusty winds to
our area. There`s a medium-high (40-80%) chance that we could
see gusts at or above 40 mph during the day on Monday with the
highest chances in our normal trouble spots for wind
(Southeastern Minnesota and Northeastern Iowa). Wrap around
showers from the exiting surface low may impact areas north of
I-94 late Monday into early Tuesday with additional
accumulations expected to be light. Some areas could see a brief
transition to snow as the temperatures cool Monday night but
impacts will be minor at best.
Warming Temperatures and More Rain Mid-Week.
As per usual with spring cold snaps, it won`t last for long with
highs by Wednesday back into the mid 50s to 60s. Another system will
be possible late Wednesday into Thursday but there is lots of
uncertainty this far out. The GFS is much more aggressive with
bringing another upper low out of the Canadian Plains and into the
Upper/Mid Mississippi Valley compared to a much more zonal EC. The
NBM seems to be leaning more towards the GFS solution with
chance to likely PoPs already forecast for Thursday. Have stuck
with the NBM for now due to significant differences in handling
of the upper levels past Tuesday. Even with the rain chances for
mid to late next week, temperatures should stay mild, generally
in the 50s to low 60s. There`s a not insignificant chance we
could see some warm temperatures at or above 70 degrees by next
weekend but there is plenty of time for this to change.
&&
.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1050 PM CDT Fri Apr 11 2025
High pressure shifted off to the southeast will result in light
winds and clear skies through Saturday morning. A deepening low
pressure shifts northeast through Saturday increasing south
winds primarily west of the Mississippi River Valley in
southeast Minnesota and northeast Iowa.
Cloud cover increases Saturday night, remaining VFR most of the
night as low chances for light rain primarily remain in central
Wisconsin. MVFR ceilings progress through the overnight
eventually affecting most of the forecast area shortly after the
TAF period through Sunday morning.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
DISCUSSION...Barendse
AVIATION...JAR
Area Forecast Discussion
National Weather Service Binghamton NY
915 PM EDT Fri Apr 11 2025
.SYNOPSIS...
Low pressure will track up the east coast tonight into Saturday
bringing a mix of rain and snow to the area. Brief high pressure
builds in behind it early next week. However, several cold
frontal boundaries and additional chances for showers move in
for the middle of next week.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
915 PM update...
Temperatures continue to fall slightly faster than forecast, so
made some minor adjustments for these changes. Scaled the
westward spatial extent of the light accumulating snow back to
the east slightly. Currently thinking is that the most favorable
time frame for accumulating snow will be between 4 AM and 9 AM.
The strongest forcing in the form of a weak, shallow band of mid
level f-gen will rotate north and east over NJ and across CT/RI
during this time. Outside this time window, there will still be
a good chance of snow as the dominant precipitation type, but
accumulation will be very difficult given the current ground
temperatures and the relatively warm 2m temperatures after 9 AM.
Still thinking the most favorable areas for accumulating
snow...anywhere from 2 to 5 inches...is across the Poconos and
Catskills above 1800 feet elevation. Winter Weather Advisories
remain the same.
620 PM update...
Temperatures are cooling and dew points are falling very
slightly faster than previously anticipated. The area of
precipitation, still well to the south, is trying to make it`s
way to the north, but outrunning the forcing that is staying
south across southern NJ and into MD and VA. Made some
adjustments to the temperature, dew point and sky cover forecast
through tonight, but kept the weather, PoPs, QPF and snow
forecast the same for now. Will evaluate the conditions and
latest guidance later this evening.
345 PM Update
Main concern in this period is a developing coastal low that
will bring a period of steady rain and higher elevation snow to
the area tonight into Saturday. Winter weather advisories have
been issued for the Catskills and Pocono region of NE PA where 2
to 6 inches of snow are expected to fall over the higher elevations.
Model trends have been for the mid level and surface low to
track further north tonight into Saturday. With a closed 700mb
low now forecast to track near Philadelphia, then over NJ on
Saturday this will bring higher QPF amounts further north into
the eastern portion of our CWA. QPF amounts over the next 24
hours is now expected to be between a half inch to one inch over
the Catskills and Poconos, diminishing to around a quarter inch
across CNY along the I-81 corridor...then less than a quarter
inch further west/north. With a close mid and upper level low it
now appears likely this system will produce enough dynamical
cooling, to change the rain over to wet snow late this evening,
with snow expanding over a good portion of the CWA late tonight
into Saturday morning. 850mb temperatures will be around -2C,
with 925mb temperatures gradually falling to around -2C by
daybreak Saturday as well. Forecast soundings from the 12z NAM
and HRRR models show just enough dynamical cooling in the
boundary layer for a changeover to snow across Sullivan,
Delaware, Pike and Wayne counties. Exactly when the changeover
will occur is slightly uncertain...but sometime between about 11
PM and 4 AM is favored in most guidance. The changeover will
occur first across the hilltops, potentially reaching the valley
floors toward daybreak Saturday. Strong lift in the 500-800mb
layer is modeled, especially on the NAM.Greatest uncertainty
will be snow ratios, and how efficiently the snow will
accumulate in and around the winter weather advisory zones. If
temperatures end up just a degree or two colder, ratios, and
therefore snow amounts could end up higher...and vice versa. The
Wyoming Valley region is a particularly tricky forecast; and
snowfall amounts look to vary greatly over short distances and
elevation changes here. In the immediate river valley(s) the
most likely scenario is for a non-accumulating rain/snow mix
Saturday morning...but once again, if it ends up just slightly
colder...more snow would mix in and some minor accumulations
could even occur in the valley itself. Surrounding high terrain
of eastern Lackawanna and Luzerne counties could easily see 1 to
4 inches of wet snow from this system. Coverage and confidence
in these amounts was not high enough for an advisory in these
two counties at this time; but something to watch closely in the
observed trends this evening.
Taking the deterministic GFS and NAM verbatim gives a good upper
end scenario. This model guidance is showing 5 to 10 inches of
snow over the higher elevations of the Catskills and Poconos by
early Saturday afternoon. While still a relatively low
probability that these amounts will be reach, this is a higher
end plausible scenario...being highly dependent on surface
temperatures. The low gradually exits Saturday afternoon, with
the precipitation tapering off to scattered rain and snow
showers for the afternoon and evening hours. High temperatures
are cool, only in the upper 30s to 40s for most locations.
Areas west of I-81 are not expected to see much if any snowfall
from this system...as the lighter intensity precipitation and
less vertical lift should keep precip type mainly rain here
overnight and through the day on Saturday. Some light snow
accumulations are expected across Susquehanna, Broome, Otsego
and Chenango counties...mainly across the higher elevations,
where up to 2 inches of wet snow may fall.
The weather starts to quiet down by Saturday night, with just a
few lingering showers that gradually end late at night. It will
be cool, with lows in the 30s.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
300 PM Update:
Upper level ridging and surface high pressure moves in on Sunday
as the low pressure system departs to the east. This will result
in a return to dry weather along with near normal temperatures
(highs in the 50s). Some morning clouds may be around, but skies
will gradually clear, allowing for partly to mostly sunny skies
by the afternoon.
A weak shortwave may spark a few isolated rain and snow showers
Sunday night west of I-81, but this system will be moisture-
starved and therefore conditions for most of the area should
remain mostly dry. Lows are expected to be in the mid to upper
30s for most of the area.
A southerly flow will develop on Monday, which will allow warmer
air to move into the area. Highs are expected to be in the upper
50s to mid 60s along with partly sunny skies. An approaching
cold front will bring increasing clouds during the afternoon and
perhaps a few isolated rain showers (mainly west of I-81). That
being said, the majority of showers should hold off until Monday
night.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
300 PM Update:
The above mentioned cold front will move through the area
Monday night which will bring more widespread showers and
potentially a few isolated thunderstorms in the evening. A
secondary cold front follows shortly after on Tuesday as an
upper trough digs into the east coast. This will allow showers
to continue Tuesday with much cooler air filtering in behind the
front. Precipitation will be mainly rain showers during the day
Tuesday, before some snow showers mix in Tuesday night. A
continued northwest flow will bring some additional scattered
rain showers to Central NY on Wednesday, before high pressure
moves back in Thursday, bringing a brief return to dry weather.
Then the next upper low may bring some more showers to the area
on Friday.
&&
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
A coastal low moves up the Mid Atlantic coast tonight into
tomorrow with widespread MVFR and IFR restrictions over the next
24 hours. ELM and ITH already have a band of showers over the
terminals with IFR cigs and vis at times. This will be slow to
move through 3Z but brief return to MVFR is possible before more
rain moves in towards 12Z with IFR and near IFR cigs returning
for much of tomorrow. ELM may get some fog development after 8Z.
AVP and BGM have the best chance at seeing some snow mix in at
times as well as see some of the heavier precipitation around
12Z into 18Z. SYR and RME will be on the northern edge of the
precipitation with lower confidence in IFR cigs. It may get cold
enough for a few hours at RME for some snow to mix in so a
tempo was added. Precipitation begins to dissipate after 18Z
with showers remaining into the evening.
Outlook...
Saturday evening and Saturday night...Lingering restrictions
likely with light rain, snow and drizzle around.
Sunday....Lingering restrictions possible in the morning, then
likely becoming VFR.
Monday...Likely VFR.
Tuesday...Scattered rain showers may bring occasional
restrictions.
Wednesday...Scattered rain and snow showers possible with
associated restrictions.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...Winter Weather Advisory until 2 PM EDT Saturday for PAZ040-048-
072.
NY...Winter Weather Advisory until 2 PM EDT Saturday for NYZ057-062.
&&
$$
SYNOPSIS...MJM
NEAR TERM...BJT/MJM/MWG
SHORT TERM...BJG
LONG TERM...BJG
AVIATION...AJG
Area Forecast Discussion
National Weather Service Dodge City KS
500 PM CDT Fri Apr 11 2025
...Updated Aviation...
.KEY MESSAGES...
- Fire weather concerns are critical on Saturday and elevated
for Sunday
- Temperatures warming to near 100 degrees for areas along the
Colorado border on Saturday
- Minor chances of rain (~20%) in northern Kansas Sunday night
and across southwest Kansas midweek
&&
.DISCUSSION...
Issued at 316 PM CDT Fri Apr 11 2025
Current RAP mesoanalysis shows significant ridging building and
moving over from off of the Rockies today. A weak surface high
pressure system is exiting the forecast area leaving calm weather
and clear skies in its` wake. Today will continue the dry stretch
for SW Kansas with highs forecasted in the upper 70s and lower 80s.
With no active headlines, fire weather risk is the most notable
aspect of the forecast over the coming days. Today, relative
humidities are expected to remain above 20% to mitigate fire
weather concerns as primarily southerly winds strengthen
somewhat through the day.
On Saturday, the fire weather risk ramps up significantly. The
SPC has much of SW Kansas in an elevated fire weather risk with
far SW Kansas in a critical fire weather day. Ensembles have
relative humidities as low as 7% along the KS/CO border. The
hold off from a fire weather headline is the winds, which will
be very borderline. Sustained winds are expected to be up to 20
mph with gusts up to 30 mph. The difficulty revolves around the
winds. When do the winds strengthen to the threshold, where is
the overlap of strong winds and low RHs, and how long do the
wind gusts maintain those speeds are all contributing to a
fairly uncertain forecast when it comes to the exact severity of
the fire weather concerns. Regardless of categories or
thresholds, fire weather impacts are expected and significant
fire weather precautions should be taken tomorrow especially in
far SW Kansas. Outside of the fire weather, temperatures are
forecast to be unseasonably warm with some areas out west at
over a 50% chance to reach 100 degrees Saturday from ensembles.
Sunday will see multiple cold fronts that will result in a cooler
day than on Saturday. This will help RH values move out of the
critical range for nearly all of SW Kansas. With the cold fronts,
multiple wind shifts are expected throughout the day with winds
ending up coming out of the north. The system has the potential to
bring light rain up around I-70 with ensembles placing rain chances
at around 20%. However, the rain showers are expected to be very
scattered with minimal accumulations. Into Monday, CAA will drop
highs further with ensembles having most of Kansas below 70 degrees.
Ensembles project a trough over the central CONUS by the middle of
the week. With it, multiple rounds of precipitation are possible
through the end of the week. No single day has a >25% chance for
rain via the ensembles and total QPF amounts through the weekend are
below 0.25" for all of SW Kansas. Uncertainty with the rain showers
will decrease into the weekend as the broader system is better
resolved.
&&
.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 500 PM CDT Fri Apr 11 2025
VFR/SKC will continue through this TAF period. South winds will
remain elevated through tonight, averaging 12-15 kts. A strong
low level jet to near 40 kts, near 2k ft AGL, is expected
overnight, 06-12z Sat. Low level wind shear was included in the
TAFs for all airports during this time range. After 15z Sat,
S/SW winds will increase at all airports, gusting 28-30 kts.
&&
.FIRE WEATHER...
Issued at 316 PM CDT Fri Apr 11 2025
Significant and near-critical fire weather conditions are
expected Saturday for far southwestern Kansas. Relative
humidities as low as 7% near the KS/CO border are depicted by
ensembles. South/southwesterly sustained winds are expected to
strengthen to around 15-20 mph with gusts up to 30 mph in the
afternoon. Some uncertainty remains regarding whether frequent
>25 mph gusts will overlap with the lowest RH values for an
extended period of time and is the reason there is not an active
fire weather headline.
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
DISCUSSION...KBJ
AVIATION...Turner
FIRE WEATHER...KBJ
Area Forecast Discussion
National Weather Service Gray ME
1051 PM EDT Fri Apr 11 2025
.SYNOPSIS...
A cutoff low will slowly move north, east of New England
through the weekend. This will bring an extended period of cool
and unsettled weather conditions. The system then moves away by
Monday with a return to drier and warmer conditions early next
week as high pressure returns. A cold front approaches from the
west Tuesday, with an upper low influencing conditions into
midweek.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
1050 PM Update...The 00Z guidance remains steady on strong Fgen
forcing lifting into southern NH and coastal SW Maine and
pivoting northwestward across portions of central to western NH.
Latest hi res guidance does suggest the band of heavy snow could
extend east bringing a burst of heavy snow across eastern NH
and western Maine after day break. Have mainly refreshed PoPs
and QPF with latest guidance which did not result in significant
changes since the last update with no changes to the Winter
Weather Advisory.
707 PM Update...After reviewing 18Z guidance and recent runs of
the HRRR have decided to issue a Winter Weather Advisory for
portions of western NH where heavy snowfall rates during the
pre-dawn hours into late morning will likely lead to difficult
travel. This recent guidance resulted in an increase in QPF and
snowfall amounts while storm total snowfall amounts may be quite
variable over short distances do to elevation dependence. These
heavy snowfall rates will be associated with a band of Fgen
forcing at H8 lifting into into southern NH and far SW Maine
around 7 AM. As mentioned in the previous discussion below, the
transition from rain to snow will also be dependent on rates
with this latest update increasing snowfall amounts in areas to
the east of the Winter Weather Advisory. This band then looks to
pivot NW spreading burst of heavy snow across the NH Lakes
Region into the Whites and points westward.
Previously...
High pressure remains positioned across the Canadian Maritimes,
as low pressure continues to organize and move northward from
the Carolinas. Cool northeasterly flow and mainly cloudy skies
between the two features continues tonight, with lows mainly
settling into the mid 30s tonight. Across northern areas, a few
more breaks in the clouds likely allow temps to drop into the
upper 20s to low 30s.
The night remains mostly dry through midnight, but the next
round of precip will begin to push in from the south after
midnight into southern New Hampshire. Precip may start off as
light rain, but as the precip becomes heavier a transition to
snow is expected. The higher elevations across southwest New
Hampshire stand the best chance to pick up 2-4" of snowfall, but
it will be highly elevation dependent and won`t accumulate on
the roads nearly as well. Elsewhere, sufficient precip rates
should allow for a burst of snow for a few hours with minimal
accumulations.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
The burst of wet snow continues to pivot northwestward through
the morning tomorrow. Accumulation efficiency drops off during
the daytime tomorrow, but even-so rates may be enough to
briefly cause a slushy layer on the roads, even in the lower
elevations. Similar to southwest New Hampshire, accumulations of
a few inches will mainly be confined to the higher terrain
through the Lakes regions of Maine and New Hampshire and into
the mountains. As precip lightens up during into the late
morning and afternoon, a transition to a showery light rain is
likely.
Showers and some drizzle continues into the night tomorrow, but
a break in the steady rain and snow is expected most of the
night. However, the next round of precip will approach from the
southeast as the weak low pressure system drifts northward
through the night. The bulk of this round will hold off until
Sunday, but some steadier precip may reach the coast by daybreak
on Sunday. Similar to the previous few rounds, precip type will
be dependent on rates, and will be even more important as temps
will be slightly warmer going into the next round.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
1050 PM Update...No significant changes with the latest NBM for
the extended. Ridging will build into the region Sunday night
into Monday for a drying and warming trend. The next trough
swings across the Northeast Monday night through Tuesday
bringing mainly rain showers. Troughing lingers into Wednesday
when colder air moves in bringing a period of snow showers in
the mountains.
Previously...
Overview:Low pressure continues up the East Coast Sunday,
passing over or just outside the Gulf of Maine. This keeps damp
conditions along at least the coast. Brief surface ridging
brings a dry and warm day Monday. The next weather system will
be broadening low pressure over northern Michigan pushing east.
This will swing an occluded/cold front through the forecast area
Tuesday before residing near New England through midweek.
Details: Broad low pressure will be morning northward up the
East Coast Sunday. Positioning takes the core of moisture well
offshore, but keeps precip chances likely along coastal areas of
the forecast area. Guidance has been very inconsistent with how
this system tracks and evolves through the late part of the
weekend. Because of this, current precip chances are rather
broad to account for a couple of possible solutions until
confidence improves.
There are two scenarios that stand out. The first is a more
prominent, stationary low deepening in the Gulf of Maine before
slowly moving northeast. This would increase QPF along the coast
and also into the Kennebec Valley region as potential banding
increases rates. This could also be a snowy outcome, albeit wet
and heavy with low ratios. The other, which leans most for the
going forecast, is a more progressive low that struggles to
pivot Atlantic moisture back towards interior portions. Because
the Sat system consolidates quicker and further out in the Gulf,
a lot of the forced moisture is instead advected north. Cyclonic
flow thus pulls in dry northerly air across the mountains,
downsloping into the interior. The coast remains dreary with
showers, but a bulk may avoid stratiform rain which will focus
around the Midcoast and Penobscot Bay region.
Deeper dry still looks to arrive Monday. This will be a nice
break between dreary systems, but clouds may still be around.
Temperatures push into the 50s, with a hint of lower 60s
possible in southern NH. At the same time, surface low pressure
will begin occluding over the northern Great Lakes, tracking
east towards New England.
Precip chances increase late Monday night through Tuesday.
Guidance has a quick moving cold front/triple point low passing the
area Tuesday morning which will bring rain or showers. Behind
the passage, winds may be gusty out of the west. Daytime mixing
could increase gust factor further, but will need to hone in on
timing for that. The low will become vertically stacked over
Quebec, but remain fairly progressive towards the Canadian
Maritimes. This looks to keep a tight pressure gradient over the
forecast area into mid to late week with potentially unsettled
and breezy conditions.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
Short Term...MVFR to VFR conditions continue into tonight. IFR
conditions move into southern terminals late tonight with rain
and snow, and spread northward through the morning tomorrow.
Mainly IFR conditions linger through tomorrow night with
showers. The best chance for more MVFR ceilings will be at HIE
later Saturday night.
Long Term...A trend from IFR to MVFR should be underway Sunday
morning with mostly rain showers across interior terminals and
south coastal terminals. RA may be more continuous north of PWM,
but remains uncertainty on coverage and if SN mixes in. All
sites trend VFR Monday, with additional restrictions possible
late Monday night into Tuesday morning.
&&
.MARINE...
Short Term...SCA conditions develop in northeasterly flow by
Saturday, and continue through Saturday night as low pressure
moves northward toward the Gulf of Maine.
Long Term...SCA condition continue Sunday into Sunday night as
low pressure pulls north towards Nova Scotia. N winds become NW
and then W Monday as the low pushes further northeast. Wave
heights likely lower through Monday afternoon with below SCA
conditions through to Tuesday morning. Here, a cold front or
weak low could bring brief SCA conditions.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...Winter Weather Advisory from 5 AM to 5 PM EDT Saturday for
NHZ005-007>009.
Winter Weather Advisory from 2 AM to 2 PM EDT Saturday for
NHZ011-015.
MARINE...Small Craft Advisory from noon Saturday to 8 PM EDT Sunday for
ANZ150-152-154.
&&
$$
SYNOPSIS...
NEAR TERM...Clair/Schroeter
SHORT TERM...Clair
LONG TERM...Cornwell/Schroeter
AVIATION...
MARINE...
Area Forecast Discussion
National Weather Service Melbourne FL
933 PM EDT Fri Apr 11 2025
...New UPDATE...
.KEY MESSAGES...
Issued at 933 PM EDT Fri Apr 11 2025
- A cold front slides southward across the Florida peninsula
tonight with isolated to scattered lightning storms in vicinity
of I-4. Isolated strong to severe storms will be possible along
and north of I-4 through 1AM.
- High fire danger is forecast Saturday afternoon and evening
over east central Florida with sensitive to near critical fire
weather conditions expected Sunday and into next week
- Drought conditions are expected to worsen as a long period of
mainly dry weather is forecast through mid-April
&&
.UPDATE...
Issued at 933 PM EDT Fri Apr 11 2025
A cold front analyzed across north Florida early this evening will
slide southward across the area tonight. Isolated to scattered
showers and storms are forecast to quickly move east-southeast
along and north of the I-4 corridor through 1 AM, with showers
quickly diminishing as the line moves further south through the
early morning hours. Pre storm analysis shows a conditional
environment for isolated strong to severe storms along and north
of I-4, and there remains some uncertainty in instability.
However, the HRRR and RAP seem to be initiating instability well
compared to radar trends west of Lake county. Should CAMs continue
to verify, a narrow nose of surface based CAPE and cold
temperatures aloft could support strong to isolated severe storms
producing coin-sized hail, frequent lightning strikes, and gusty
winds. The greatest storm hazards look to be focused north and
west of I-4.
A drying trend is forecast behind the front, and west winds veer
northwest. Gusty post frontal conditions will promote fire
sensitivities across east central Florida tomorrow, and a Fire
Weather Watch continues for all east central Florida counties.
&&
.PREVIOUS DISCUSSION...
Issued at 355 PM EDT Fri Apr 11 2025
Currently-Saturday... Local radar imagery shows dry weather over
east central Florida. GOES-16 satellite imagery shows mostly clear
to partly cloudy skies. A cold front is situated over the
southeastern US and northern Florida which extends from low pressure
(~1012mb) over the North Carolina coast. Temperatures are currently
in the mid 70s to mid 80s with dew points in the mid 40s to near 60.
Winds are out of the west-southwest at 5-15mph with gusts to around
20mph over the inland counties. Winds have begun to back southeast
at 5-15mph with gusts to 20-25mph along the east central Florida
Atlantic coast with the east coast sea breeze.
Isolated to scattered offshore moving showers (20-50%) and lightning
storms are expected tonight mainly after 8pm with the greatest
potential for any strong storms along and to the north of Melbourne
to Lake Kissimmee from 9pm to 2am. Isolated to widely scattered
showers (20-30%) and lightning storms are forecast to the south of
the aforementioned areas from 1am to 5am. Hi-res guidance indicates
that instability will increase as the cold front approaches east
central Florida with MUCAPE at 500-1,200 J/kg coupled with 40-60kts
of 0-6km bulk shear and 500mb temperatures at -14C to -18C.
Additionally, moisture has the potential to be a limiting factor for
severe storm potential with forecast PWATs in the 0.9-1.25" range
tonight. Any strong lightning storms that develop will be capable of
wind gusts up to 40-50mph, occasional to frequent lightning, and
moderate to brief heavy rainfall. A Marginal Risk for severe storms
exists over Lake, Volusia, Seminole, and northwestern Orange
counties where the potential exists for wind gusts up to 60mph (5-
14% risk) and hail up to 1" diameter (5-14%). Low temperatures in
the low 50s to low 60s are expected with partly to mostly cloudy
skies.
Dry weather is expected on Saturday behind the cold front as broad
high pressure (~1022mb) builds over the eastern US. North-northwest
winds at 10-15mph with gusts to 20-25mph are expected. Cooler
temperatures are forecast with highs in the 70s to near 80 degrees
under
Sunday-Monday... Dry weather will continue Sunday and into next week
as high pressure (~1020mb) builds over the southeastern US before
becoming centered over the state of Florida and the western Atlantic
on Monday. Afternoon highs in the mid 70s to low 80s are forecast
Sunday. A warming trend is expected into next week with highs in the
low to upper 80s on Monday. North-northeast winds at 5-10mph are
forecast Sunday. Generally light south-southwest winds are expected
to increase and back east-southeast at 10-15mph into the afternoon
on Monday as the east coast sea breeze moves inland mainly east of
the Orlando metro. Lows in the upper 40s to near 60 degrees are
forecast each morning.
Tuesday-Thursday... A cold front is forecast to move east- southeast
over central Florida Tuesday night. Guidance indicates that the
front will extend from low pressure (~992mb) over the northeastern
US and southern Canada Tuesday night into early Wednesday. Global
models don`t show much precipitation with this front, however the
conditions will be similar to Friday night`s cold front with PWATs
in the 0.90-1.25" range, as well as low instability and moderate to
high bulk shear. Therefore, isolated showers (~20%) are forecast
Tuesday night into early Wednesday mainly north of Melbourne to Lake
Kissimmee. Afternoon highs in the mid 80s to near 90 degrees are
forecast Tuesday, the mid 70s to mid 80s are forecast Wednesday, and
the upper 70s to upper 80s on Thursday. Lows generally in the 50s to
mid 60s are forecast.
&&
.MARINE...
Issued at 241 PM EDT Fri Apr 11 2025
Currently-Saturday... Poor to hazardous boating conditions are
expected into Saturday as a cold front moves east-southeast over the
east central Florida Atlantic waters tonight into Saturday morning.
Isolated to scattered (20-70%) offshore moving showers and lightning
storms are forecast mainly after 9pm. Any strong storms that develop
will be capable of frequent lightning, wind gusts to 40-50mph, and
small hail. A Marginal Risk for severe storms exists over nearshore
Volusia county where the potential exists for wind gusts up to 60mph
(5-14% risk) and hail up to 1" in diameter (5-14% risk). South-
southwest winds at 10-15kts are expected to increase and veer
northwest into Saturday morning at 15-20kts. 3-5ft seas are expected
to increase to up to 6ft over the Gulf Stream overnight into
Saturday where Small Craft Should Exercise Caution.
Sunday-Tuesday... High pressure (~1020mb) will build over Florida
and the western Atlantic into next week. Favorable boating and dry
conditions are expected. Northeast winds at 6-12kts are forecast
Sunday before winds veer south-southeast into Monday afternoon at
10-15kts. South winds at 10-15kts are forecast on Tuesday. Seas
to 2-4ft are forecast with up to 5ft in the Gulf Stream.
&&
.AVIATION...
(00Z TAFs)
Issued at 808 PM EDT Fri Apr 11 2025
A cold front analyzed across north Florida slides southward
across the Florida peninsula tonight. Prevailing VCSH from VRB
northward ahead of and along the front. TSRA TEMPOs included
across the interior and at DAB where peak CIG/VIS impacts are
forecast along the immediate line of storms. West winds around 10
kts ahead of the front veer northwest as the boundary passes. Wind
gusts up to 20 kts return to most terminals after 15Z tomorrow.
Dry conditions build behind the front.
&&
.FIRE WEATHER...
Issued at 355 PM EDT Fri Apr 11 2025
Critical fire weather conditions are expected into this evening
with a Red Flag Warning in effect until 7pm for Lake, Volusia,
Orange, Seminole, Osceola, and northern Brevard counties.
Sensitive fire weather conditions are expected to the south of
those counties.
Critical fire weather conditions are expected on Saturday. A Fire
Weather Watch is in effect from 1pm to 7pm Saturday. Fire-
sensitive weather conditions will continue well into the forecast
as much drier air is expected over Florida this weekend into early
next week. Minimum RH values from 25-35% are forecast each day
through mid week next week over east central Florida, especially
over the interior. Winds will be relatively stronger on Saturday
(NW 10-15 mph) and Tuesday (WSW 8-14 mph) compared to Sunday and
Monday.
Very good to excellent dispersion is forecast today and Saturday.
.PRELIMINARY POINT TEMPS/POPS...
DAB 55 75 51 76 / 40 0 0 0
MCO 58 77 53 81 / 40 0 0 0
MLB 59 78 55 77 / 30 0 0 0
VRB 59 78 52 78 / 20 0 0 0
LEE 55 76 52 80 / 40 0 0 0
SFB 57 78 53 80 / 40 0 0 0
ORL 59 78 55 81 / 40 0 0 0
FPR 58 79 51 79 / 20 0 0 0
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 55 75 51 76 / 40 0 0 0
MCO 58 77 53 81 / 40 0 0 0
MLB 59 78 55 77 / 20 0 0 0
VRB 59 78 52 78 / 20 0 0 0
LEE 55 76 52 80 / 40 0 0 0
SFB 57 78 53 80 / 40 0 0 0
ORL 59 78 55 81 / 30 0 0 0
FPR 58 79 51 79 / 10 0 0 0
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...Fire Weather Watch from Saturday afternoon through Saturday
evening for FLZ041-044>046-053-058-141-144-154-159-164-247-
254-259-264-347-447-547-647-747.
AM...None.
&&
$$
UPDATE...Law
AVIATION...Law
Area Forecast Discussion
National Weather Service Marquette MI
1158 PM EDT Fri Apr 11 2025
.KEY MESSAGES...
- Rising temperatures are expected into the weekend with daytime
high reaching the 50s on today and low-60s Saturday/Sunday.
- Next system brings rain and a mix of rain and snow Sunday and
Monday. Temperatures cool enough late Monday into Tuesday for snow
while the system pulls away.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 122 PM EDT Fri Apr 11 2025
GOES-East Day Cloud Phase RGB shows the morning`s fog and low clouds
dissipating over the Keweenaw and to a lesser extend over Lake
Superior while shallow cu fields are developing along the state line
in Gogebic and Iron counties. RAP analysis shows ridging aloft
moving from the Plains towards the Great Lakes, leading to a 1026mb
high pressure centered over Iowa. This high pressure will be the
dominant feature of the short-term forecast as HREF hourly PoPs are
10% or less across the UP now through 12Z Saturday. Temperatures are
climbing a little faster than originally expected with south-central
Marquette County and interior Alger County already seeing some 50
degree temperatures with 40s observed just about everywhere so far
except for the mainland portion of Keweenaw County.
Tonight, expect dry conditions to also lead to little to no fog
development as dry surface-layer air keeps temperatures from quite
reaching their dew points. The HREF, the most aggressive suite from
last night`s fog setup, still holds 20-40% fog probabilities for
Baraga/Iron counties and east with higher chances over the east half
of Lake Superior, though the HREF does tend to be a bit too
aggressive over the UP with fog formation (especially near the
water). LAMP probabilities of fog have fallen from around 20% to
near 0 for the Ironwood area, while the Houghton and Marquette areas
maintain around what the HREF predicts. The Euro ensemble shows
virtually no visibility restrictions overnight tonight into Saturday
morning. Therefore, given known biases, this forecast will reflect
no fog, though trends should be monitored for the overnight package
in case more boundary layer moisture can be realized. Expecting lows
tonight around the 30 degree mark.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 247 PM EDT Fri Apr 11 2025
Broad scale ridging will breakdown Saturday as a surface high over
the region shifts east and surface low tracks into northwest Ontario
while a few waves over the northern Plains organize. Increasing
convergence by Saturday night will help support rain moving into the
western portions of the forecast area. As the night progresses and
we move into Sunday, increasing isentropic ascent looks ahead of a
surface low upstream will support additional rain showers. Upstream
on Sunday, the surface low will roll into the midwest. By Monday
morning, the low deepens over or near Lake Superior as a more robust
shortwave presses through the Upper Great Lakes. The generalized
breakdown of events with this feature`s passing from here involves
increasing colder air wrapping around the surface low through the
day Monday, which would support a rain to rain/snow to snow
transition of any precipitation through the day. The low then pushes
eastward into Ontario/Quebec Monday night while lake effect or lake
enhanced snow showers continue downwind into Upper Michigan.
Ensemble means of the GEFS and EPS place the deepening low over
central or eastern Lake Superior by Monday morning, but clustering
shows solutions spanning anywhere from just north of Lake Superior
to the "thumb" of the Lower Peninsula. The same geospatial and
temporal spread is noted among their deterministic counterparts,
which impacts the confidence of and timing of dry slotting Monday
morning after the initial precip wave and where the low`s
deformation zone lines up Monday night. Will note that the latest
NAM guidance is farther NW still, taking a track from the Arrowhead
to north of Lake Superior into Monday. There`s also spread in the
850mb airmass wrapping around the low, which brings into question
whether or not the airmass will be cold enough to support lake
effect snow or if the synoptic/mesoscale hybrid of lake enhancement
is expected. Should the deformation zone press into the region
Monday night, there is the potential for impactful wet snow. This
will be worth monitoring as we move closer to the event. Another
high will press east toward the area Tuesday, which will help
diminish shower activity through the day. Following a dry midweek
period, another low pressure system ejects out of the Plains
Thursday and heads towards the Great Lakes into Friday. This will
bring our next potential for precipitation as early as Thursday
morning.
Daytime highs on Saturday and Sunday may break into the 60s across
the interior west half while everyone else tops out in the upper 40s
and low 50s. With the system over the region Monday, we may be hard
pressed to warm much more than the upper 40s or low 50s. Coldest day
in the period will be Tuesday, with highs mostly in the 30s and low
40s. Should rebound back into the 40s and 50s for the rest of the
week. Overnight lows Saturday and Sunday should be mostly above
freezing, then fall back below or near freezing Monday night.
&&
.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 1158 PM EDT Fri Apr 11 2025
Time cross sections continue to indicate a dry air column, so will
continue to keep mention of fog out of TAFs this morning. Did,
however, introduce PROB30s for visibility restrictions in any rain
showers late in the TAF period as a surface low traverses northern
Ontario later today. Otherwise, expect southerly winds under 10 kts.
&&
.MARINE...
Issued at 247 PM EDT Fri Apr 11 2025
High pressure will keep light winds over the region through
Saturday. By then, an organizing low upstream will press closer to
the region, then deepen near or over Lake Superior on Monday. Expect
winds to gradually increase Sunday and Sunday night to near 20kts.
With the deepening low over or within the vicinity of the lake
Monday, winds are expected to increase through the day as increasing
pressure gradient and colder air filters into the region. Ensemble
guidance continues to highlight increasing gale probabilities Monday
evening into Tuesday morning across central and eastern Lake
Superior. Latest guidance continues to suggest 70% or higher
probabilities of gales to 40kts with ~30% to 45kts. Significant wave
heights could build to 10-14 feet by Tuesday morning east of the
Keweenaw. Expecting conditions to slowly relax through the day
Tuesday from west to east, with gales falling off Tuesday evening
and winds finally falling below 20kts Wednesday morning.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
Dense Fog Advisory until 3 AM EDT Saturday for LSZ266-267.
Lake Michigan...
None.
&&
$$
SHORT TERM...GS
LONG TERM...LC
AVIATION...TDUD
MARINE...LC
Area Forecast Discussion
National Weather Service Raleigh NC
815 PM EDT Fri Apr 11 2025
.SYNOPSIS...
Low pressure off the VA coast will continue to shift northeast
through early Saturday. Canadian high pressure will then build
across and offshore the Middle and South Atlantic later Saturday
through the rest of the weekend, ahead of a warm front that will
move across the region on Monday.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 815 PM Friday...
As of 8pm, surface low pressure was just off the Norfolk coast.
Thunderstorms have moved through southeastern counties in the last
hour, and it appears that most of the precipitation in this area
will remain along the coast. Back to the northwest, a broken line of
showers extends from the Triangle back into the Triad, although with
no instability here, lightning has not been observed. Showers should
continue to decrease in coverage through the evening, with little
more than a passing shower possible after midnight northeast of the
Triangle. With the upper low remaining over eastern Virginia, mostly
cloudy skies will persist through the night. Previous discussion
follows.
As of 204 PM Friday...
Observations show the 700 mb low over the northwest Piedmont, with
the surface low off the northern Coastal Plain. These two features
are quite evident on satellite imagery and regional/local radar. The
last few runs of the HRRR have done a good job the latest trends
seen on radar, with most convection along the Triangle and northern
Sandhills, and stratiform rain over the Triad. This activity should
continue to shift east and southeast into the late afternoon to
early evening, with activity shifting east of the Coastal Plain by
early evening. Another area we are watching is a batch of showers
and scattered storms currently west and southwest of Charlotte. All
of this activity should continue to track ESE into the late
afternoon and early evening hours across the southern Piedmont and
Sandhills to southern Coastal Plain tied to the 700 mb circulation.
This activity, along with the current storms on radar moving into
the Coastal Plain, will likely have the best chance to produce large
hail. These areas may feed on some 500 to 1000 J/kg of CAPE in the
warm sector and combine with the deep-layer shear in place. The
severe threat should diminish rather abruptly after 6-8 pm with loss
of heating and as a cold front starts to sweep through from the WNW
as the surface low tracks offshore of VA overnight.
Temperatures behind the front tonight will drop into the low 40s NW
to upper 40s SE. Even though rain chances should diminish by late
this evening, wrap around low-level moisture will favor ongoing low
stratus that will be slow to clear out. Cannot rule out some
isolated drizzle as well. Some fog may develop over the Triad in the
early overnight period as this area has remained soggy and cloudy
most of the day.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
As of 100 PM Friday...
As the surface low shifts off the DELMARVA coast early Saturday
morning, a few wrap around isolated showers could be possible in the
afternoon. All the precip will dissipate by sunset as surface high
pressure builds in from the TN valley. Temperatures during the day
will range from the upper 50s north to low/mid 60s elsewhere. Lows
will range from upper 30s to low 40s.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
As of 115 PM Friday...
Sunday and Monday will be dry as upper level ridge builds across the
Mid-Atlantic region. Northwest flow on Sunday will result in well
below normal temperatures with highs in the mid 60s, and a few spots
in the south reaching the low 70s. Clear skies Monday, along with
southwesterly flow will promote more near normal temps with highs in
the 80s and lows in the 60s.
By Tuesday another upper level trough will be moving across the MS
valley and into the Mid-Atlantic bringing another chance of precip.
Models have continued to trend on the dry side as the front moves
across the region. But with good PW values ranging from 1-1.5 inches
cant rule out some scattered showers in the afternoon with daytime
heating. Best chance for precip for now will be along and east of
the US1 corridor with light accumulation amounts. Will have to keep
an eye on the model trends with this system over the next few days.
After the front exits a back door cold front will reinforce cooler
air across the region with highs in the mid 60s to low 70s Wednesday
and Thursday, and lows in the 40s to 50s.
Late Thursday through Friday models are showing another trough move
across the region. Most long range models are showing a chance for
showers and storms late Thursday through Friday. Temperatures will
largely depend on the timing of the frontal passage but highs will
be in the 70s with lows in the 40s.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
As of 720 PM Friday...
Light rain from the Triad terminals to RDU will continue to drift
southward with a weakening trend as they approach the FAY area
through 02z before dissipating completely. MVFR cigs across the
northern terminals will more-or-less persist through the overnight
hours; although some lifting to low-end VFR will be possible in the
Triad when dry downsloping flow scours out low-level moisture. High-
end MVFR cumulus will be possible with diurnal heating late Sat
morning before lifting to VFR through mid-afternoon. Spotty, shallow
showers will be possible (5 to 20%) at RDU, FAY, and RWI from 20z to
02z, but could occur as early as 18z; brief MVFR vsby restriction
would be the main aviation concern. Surface winds will generally be
light (5 to 15 kt) out of the north to northwest through the TAF
period.
Outlook: VFR should prevail through the period, though gusty winds
of 25-35 kt are possible Mon and Tue along/ahead of a cold frontal
passage. Isolated showers are possible as well with the front.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Green/MWS
NEAR TERM...Green/Kren
SHORT TERM...CA
LONG TERM...CA
AVIATION...Swiggett/Kren
Area Forecast Discussion
National Weather Service Reno NV
1257 PM PDT Fri Apr 11 2025
.KEY MESSAGES...
* Above normal temperatures continue through next week.
* Brush by cold front brings light showers late tonight and breezy
periods Saturday.
* Streamflows will increase as a result of warming but no
appreciable flooding expected.
&&
.DISCUSSION...
* Fast moving upper wave and attendant cold front will bring
isolated showers to NE Cal overnight into early Sat AM. HRRR shows
100-200 elevated CAPE with HREF indicating 10-30% odds for t-
storms from Lassen NP to Susanville/Alturas.
* Same front will bring breezy N/NW winds on Saturday, mainly for
western and northern NV. Most breezes should be on the order of 20-
30 MPH gusts. NBM shows 20-30% probability for peak gusts over 45
MPH in areas such as Gerlach, Lovelock, and Fallon. Blowing dust
could be an issue Saturday given recent dry weather. Pyramid and
Walker Lakes will get choppy Saturday afternoon/evening.
* Temps will take a slight dip this weekend, but warm back up to
well above normal next week. Starting Monday NBM shows meaningful
probabilities for max temps above 80 in W Nevada (60% or higher).
This coupled with above freezing lows in mountains (e.g. Sonora
Pass 75% odds for lows above 35), should yield increases in
snowmelt driven streamflows most of next week. Flooding is
unlikely, but any flooding should be minor and brief, as temps are
warm but not "heatwave warm".
* Deterministic models are showing some weak waves moving into
CA/NV next week. One in particular on Tuesday seems to have more
potential of kicking off showers over the high terrain, and
perhaps a t-storm or two. 10-20% odds but worth watching.
-Chris
&&
.AVIATION...
* VFR conditions for the most part through the weekend.
* Brush by cold front will bring breezy W/SW winds this afternoon
and N/NW winds on Saturday. Mostly gusts 20-25 knots. Could be
some blowing dust visibility restrictions between NFL-LOL-WMC
Saturday. Flow aloft sufficiently fast for LLWS and mountain wave
turbulence tonight between 6z-18z, mainly in the Sierra.
* Latest HREF/HRRR showing potential for a band of showers and
possibly t-storms from Lassen Peak to SVE/AAT late tonight between
6z-15z. Could see localized MVFR conditions, about a 20-30%
probability.
-Chris
&&
.REV Watches/Warnings/Advisories...
NV...None.
CA...None.
&&
$$