Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/16/19
AREA FORECAST DISCUSSION
National Weather Service Albany NY
953 PM EST Fri Nov 15 2019
A cold front will cross the region overnight.
Dry and cold conditions will follow in the wake of the front
on the weekend. A coastal storm may bring a wintry mix or rain
to portions of the region Sunday night into Monday.
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
As of 950 PM EST...A cold front continues to move across the
region early this evening with the scattered snow showers and
flurries shriveling up due to the lack of low-level moisture and
the strong inversion on the 00Z KALY soundings. An isolated snow
showers or flurry is possible the next couple of hours with a
stray dusting, but the activity should cease based on the radar
and 3-km HRRR and NAMnest trends. Low-level cold advection will
continue with temps falling into the teens with a few lower 20s
over the mid Hudson Valley. Some single digits are possible in
the southern Adirondacks, Lake George Region and southern VT.
North to northwest winds of 5 to 15 mph are likely with a few
gusts 20-30 mph with the frontal passage.
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
Saturday, should be mostly sunny and dry, however there could be
a narrow band of clouds and perhaps snow showers or flurries in
the morning across portions of Washington County and western
Bennington County, due to a potential response from Lake
Champlain. Will have to watch radar and NYS mesonet trends
closely, in case some minor accumulations occur over isolated
areas. Otherwise, cold with decreasing wind, with highs mostly
in the teens and 20s across northern areas and higher terrain,
with lower/mid 30s in valley areas.
Saturday night should be mostly clear and very cold as winds
decrease/decouple along with lingering snowpack in northern
areas. Expect low temps to drop to between zero and 10 below
across the southern Adirondacks, zero to 10 above southern VT
and the Saratoga/Lake George region, with mainly teens
Sunday, confidence levels decrease in forecast beginning Sunday,
as low level moisture from the offshore storm system potentially
draws north to northwest into the region by late in the day.
09Z/SREFs actually indicate possibly light precipitation
developing across SE areas before sunset. For now, have kept out
mention of precipitation, although trends will need to be
watched over the weekend in case timing and areal coverage of
late day precipitation increases. Otherwise, still chilly with
highs mainly in the 30s for valleys, 20s across higher
Sunday night-Monday, high degree of uncertainty for this time
period, track of offshore storm system remains uncertain, as
does the potential interaction of low level moisture around the
storm which could draw further north/west into portions of the
region, and additional upper level energy approaching from the
southwest. Latest 12Z/EC has trended even farther east with
system than 00Z/15 cycle, keeping conditions mainly dry during
this time period, while the GEM/NAM bring precipitation into the
region Sunday night into Monday. Thermal profiles suggest
warming aloft, favoring mainly sleet/freezing rain initially
once precip develops, and with mainly light intensity expected,
potential diabatic cooling of column may remain minimal (thus
preventing change over to snow). Will be indicating chances for
freezing rain late Sunday night into Monday morning, changing to
plain rain by Monday afternoon for most areas, although can not
rule out freezing rain lingering longer in some higher terrain
areas and even some valley areas north of I-90 in NY, and the CT
River Valley in southern VT. Ice accretion looks relatively
light, generally less than one tenth of an inch, however the
very cold temps from this weekend could allow for icing to occur
rather easily on untreated surfaces during the Monday morning
commute. So, despite light amounts, impacts for travelers could
be quite high Monday morning. Lows Sunday night mostly in the
20s to around 30, with temps expected to gradually rise from S
to N overnight. Highs Monday mainly in the 30s, although may
only reach the lower 30s in some areas of the southern
Adirondacks, the Lake George region, and areas adjacent to the
CT River Valley in SE VT.
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
The extended forecast period will continue to feature a mean longwave
trough over the Northeast. Low pressure near the New England Coast
opens the long term with mixed precipitation transitioning to rain
and snow, as an upper low moves over the region. More tranquil
weather moves into the region for late WED-THU.
Monday night into Tuesday...There continues to be some uncertainty
concerning the location and the position of the coastal low Monday
night into Tuesday. However, another northern stream trough looks
to be moving in from the north and west with a transition of any
light mix of rain/sleet/freezing rain to some snow by Tue morning
with light accums of a coating to less than an inch over the higher
terrain. The cyclonic vorticity advection with the short-wave will
produce some isolated to scattered rain and snow showers in the
afternoon. Temps will be below normal, but not as cold as this week.
Lows will be in the mid 20s to lower 30s. Highs on Tuesday will be
in the upper 30s to lower/mid 40s in the valleys and highs in the
upper 20s to mid 30s.
Tuesday night into Wednesday...A weak frontal boundary moves across
the region with some isolated to scattered rain and snow showers
depending on how warm the boundary layer gets. There is not a lot
of moisture with this front and its associated mid-level trough.
Temps will be similar to Mon night into Tuesday with perhaps some
slightly cooler temps WED due to the low-level cold advection in the
wake of the front. Highs in the upper 20s to mid 30s over the mtns,
and upper 30s to lower/mid 40s in the valley.
Wednesday night into Thursday...High pressure builds in from the TN
Valley and the Southeast with mainly fair, cold and dry weather
before a warm front approaches from the lower Great Lakes late in
the day. Lows fall back into the 20s to lower 30s. Some sunshine
before thickening and lower clouds will allow for highs to trend
close to normal late November readings.
Thursday night into Friday...A low pressure system and cold front
will bring widespread chances for rain and snow showers to close the
week. Some lake and gulf moisture may be tapped, but the system
looks very progressive to keep amounts light. Temps looks slightly
below normal to normal to close the week.
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
A cold front will move across the region early this evening with
a reinforcing shot of arctic air. High pressure will build in
from southeast Canada and the Great Lakes Region tomorrow.
VFR conditions are expected most of the next 24 hours ending
00Z/SUN at KALB/KGFL/KPSF/KPOU.
A cold front will bring some isolated to scattered snow showers
to locations north of KALB-KPSF between 00Z-05Z/SAT. The best
chance of brief MVFR conditions is at KGFL where we have a TEMPO
group for MVFR cigs/vsbys with snow showers between 01Z-03Z.
Further south, VCSH groups were used 01Z-04Z/SAT at KALB with
some high MVFR cigs. The moisture dries out and cigs may get to
3.5-4.0 kft AGL prior to midnight for KALB/KPSF, but then the
skies will clear quickly with just some mid or high clouds near
KPOU and scattered stratocumulus.
Overall, clear or mostly clear skies are likely after 07Z/SAT at
all the sites and continuing for the rest of the TAF cycle.
The winds will be west to northwest at 8-14 kts with some gusts
20-25 kts at KALB/KPSF. The winds will veer to the
north/northeast after 06Z/SAT at 5-10 kts and will continue
through the morning into the afternoon.
Saturday Night: No Operational Impact. NO SIG WX.
Sunday: No Operational Impact. NO SIG WX.
Sunday Night: Moderate Operational Impact. Chance of FZRA...SLEET.
Monday: Moderate Operational Impact. Chance of RA...FZRA.
Monday Night: Moderate Operational Impact. Chance of RA...SN...SLEET.
Tuesday: Low Operational Impact. Slight Chance of SHRA...SHSN.
Tuesday Night: Low Operational Impact. Slight Chance of SHRA...SHSN.
Wednesday: Moderate Operational Impact. Chance of SHRA...SHSN.
An arctic cold front will cross the region tonight, bringing
some snow showers to northern areas. Dry and cold conditions
will follow in the wake of the front for Saturday through
Sunday. A coastal storm may bring a wintry mix or rain to
portions of the region Sunday night into Monday.
Wind gusts of 25 to 35 mph will be possible with the frontal
passage early tonight, with some gusts up to 25 mph lingering
until late tonight.
No hydro issues are anticipated through early next week.
A passing Arctic cold front will return another round of cold
temperatures for the weekend. Little precipitation is expected
with this boundary and what little does occur will be only
across northern areas and will be in the form of snow showers.
Next chance for widespread precipitation looks to be early to
mid next week thanks to a coastal storm and exact amounts and
precipitation types are still uncertain at this time, although
current indications favor light amounts some of which may be in
With the cold temperatures in place, some ice will continue to
form on shallow bodies of water. Otherwise, river and streams
levels will generally hold steady into early next week.
For details on specific area rivers and lakes, including latest
observed and forecast river stages and lake elevations, please
visit the Advanced Hydrologic Prediction Service /AHPS/ graphs
on our website.
Area Forecast Discussion
National Weather Service La Crosse WI
600 PM CST Fri Nov 15 2019
.SHORT TERM...(This evening through Saturday)
Issued at 323 PM CST Fri Nov 15 2019
At 2 PM, broken high clouds were found along and south of
Interstate 94. Elsewhere, skies were mainly sunny. Temperatures
ranged from 35F at Medford, WI to 46F in Austin, MN.
For tonight, there continues to be uncertainty on whether low
clouds will once again develop. The SREF shows that these clouds
would develop across southeast Minnesota, northeast Iowa, and
southwest Wisconsin. Meanwhile, the RAP would have it mainly in
eastern Wisconsin. While the low cloud forecast are uncertain,
the models are in good agreement that mid and high clouds will
move into the area. With very dry air over central and north-
central Wisconsin, temperatures will drop off quickly this
evening and be around 20 by midnight and in the teens overnight.
Elsewhere, temperatures will be in the mid and upper 20s.
The Saturday high temperatures will be highly dependent on whether
the low clouds develop or not. Due to this, opted to stay close to
the 50th percentile on high temperatures (mid- and upper 30s). If
they do not develop, we will likely be more around the 75th
percentile which would have high temperatures around 40 degrees.
.LONG TERM...(Saturday night through Friday)
Issued at 323 PM CST Fri Nov 15 2019
From Saturday night into Sunday, a low pressure system will move
east through the region. The models are in general agreement that
this precipitation will move into the area around or after
midnight and then continue into Sunday afternoon or evening. The
soundings are saturated and the boundary layer is cold enough that
the precipitation will be mainly snow on Saturday night and then
transition to a mix as the boundary layer warms and there is a
loss of ice aloft as the dry slot moves into the area. There could
be even a brief period of freezing drizzle. Snow amounts will
range from around a half inch in northeast Iowa and southwest
Wisconsin to around 2 inches north of Interstate 94.
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 559 PM CST Fri Nov 15 2019
VFR conditions are expected tonight through the day Saturday.
Mainly VFR high clouds are expected tonight, with winds becoming
more southeast as the night wears on. There is potential for some
low clouds or fog to form over areas with recent snowpack melt, but
at present confidence in this is low as it looks like increasing
winds just off the surface overnight will be enough to keep fog/low
clouds at bay. This will have to be watched overnight, however.
Tight pressure gradient between high pressure moving to our east and
incoming area of lower pressure will lead to gusty southeasterly
winds for Saturday, with gusts from 20 to 25 knots possible. Mainly
high clouds are expected during the daytime ahead of the next
system, which looks to spread in rain/snow chances and lower clouds
later Saturday night.
Area Forecast Discussion
National Weather Service Green Bay WI
614 PM CST Fri Nov 15 2019
Updated aviation portion for 00Z TAF issuance
.SHORT TERM...Tonight and Saturday
Issued at 210 PM CST Fri Nov 15 2019
The latest RAP analysis and satellite/radar imagery show surface
high pressure over northwest Ontario and a weak cold front
settling over the southern part of the Badger state. Some low
clouds have pushed into far northern WI off Lake Superior, but
otherwise, mostly clear skies prevail across northern Wisconsin.
Meanwhile, the next system is moving into the Pacific Northwest.
As this system draws closer to the region, forecast concerns
mainly revolve around clouds and temps.
Tonight...The high pressure system will slide to the southeast
across the far northern Great Lakes. After a mostly clear start to
the evening, winds will be veering to the northeast and then
southeast through the night. Delta T`s will be more than
sufficient for lake clouds to move inland over the lakeshore late
this evening, and possibly move into the Fox Valley and Bayshore
areas after midnight. Forecast soundings look quite dry above
925mb, so don`t think will see any precip. Otherwise, will see mid
and high clouds increase through the night ahead of the next
system. Some low clouds may also redevelop over north-central WI
late as moisture returns north. Due to onshore flow and increasing
clouds, temps should remain relatively mild and range from the
mid teens to mid 20s.
Saturday...High pressure will continue to exit east of the region
while the next front moves across the Dakotas. Low clouds are
expected to remain over parts if not most of the area during the
morning. Some erosion of the low clouds may occur with heating
during the late morning and afternoon. It will likely remain a
mostly cloudy day though, as a result of a blanket of mid and
high clouds. Highs should remain mild despite the cloud cover and
range from the middle to upper 30s.
.LONG TERM...Saturday Night Through Friday
Issued at 210 PM CST Fri Nov 15 2019
Initially, a relatively amplified and progressive flow to exist
across the CONUS that will persist into the start of next week,
before a new upper trough hits the West Coast and eventually
becomes a closed upper low off the southern CA coast. This results
in a split flow with a northern stream system impacting the Great
Lakes late Wednesday night/Thursday. Temperatures should be mainly
at or slightly below normal.
As a cold front and mid-level shortwave trough move into the Upper
MS Valley Saturday night, look for clouds to thicken over
northeast WI with a chance of light snow reaching central WI by
daybreak. A prevailing south wind, combined with the clouds, will
prevent temperatures from falling much through the night. Min
temperatures to mainly be in the 25-30 degree range. This front/
trough push into the western Great Lakes region on Sunday with
sufficient lift/forcing/moisture present to make light snow or a
rain/snow mix likely across the forecast area. This system is
progressive and with temperatures at or above freezing,
accumulation numbers should be on the light side (1-2 inches north
and central, less than an inch east-central).
Any rain/snow mix over eastern WI should transition to all snow by
Sunday evening as temperatures cool after sunset. The bigger
forecast problem could be the potential of freezing drizzle as a
loss of ice aloft occurs behind the system. If freezing drizzle
were to occur, this would impact the Monday morning commute,
especially on untreated roads, bridges and overpasses. Min
temperatures to range from the middle 20s north-central WI, to
around 30 degrees east-central WI. A very weak surface ridge to
drift across WI on Monday and may not have enough dry air or
subsidence to break up the clouds. Thus, mostly cloudy skies to
prevail through the day with max temperatures primarily in the
middle to upper 30s.
After a quiet, albeit cloudy Monday night, models show a weak
shortwave trough to dive southeast through Lake Superior toward
the eastern Great Lakes region on Tuesday. This system would bring
a chance of a rain/snow mix or all rain to northeast WI as
temperatures reach the middle 30s to around 40 degrees. As a new
upper trough digs south over the western CONUS mid-week, a modest
downstream upper ridge to develop over the central CONUS. At the
surface, another weak surface ridge to pass through WI Tuesday
night and reside to our east on Wednesday. There could be a brief
break in the cloud dover as the ridge moves by, however clouds are
expected to return on Wednesday as a return flow develops and WAA
overspreads WI. From all indications, Wednesday could be the
warmest day of the extended forecast as max temperatures reach
around 40 degrees north-central, lower to middle 40s east-central
The western CONUS upper trough becomes a closed upper low off the
southern CA coast, the mean flow becomes split east of the
Rockies. a piece of energy ejects into the central Plains
Wednesday night with an inverted surface trough to extend
northeast into the Great Lakes. Southwest winds aloft to pull gulf
moisture northward into WI where convergence along the surface
trough should allow for precipitation to break out over northeast
WI. Temperatures should cool enough by the time any precipitation
were to begin, such that snow would be the main precipitation
type. On Thursday, an area of low pressure to ride northeast along
the eastward moving surface trough and combine with a northern
stream shortwave trough, to continue the precipitation chances
over the area. Precipitation type may become an issue as
temperatures are mild initially, but colder air spilling into WI
through the day would transition the precipitation to all snow.
Plenty of details will need to be sorted out (location of surface
trough, track of low pressure, timing of shortwave trough, amount
of moisture, etc.), thus confidence is too low yet to even give a
snow estimate on this system.
This system quickly exits by Thursday evening, leaving cooler air
and a northwest wind over WI. This may lead to some lake effect
snow showers over north-central WI as 8H temperatures over western
Lake Superior drop to around -12C. A ridge of high pressure to
then build across WI on Friday, allowing skies to become partly
cloudy. Max temperatures Friday to be around 30 degrees north,
lower to middle 30s south.
.AVIATION...for 00Z TAF Issuance
Issued at 613 PM CST Fri Nov 15 2019
VFR conditions prevailed across the area during the afternoon
hours. As winds veer to the northeast, look for lake effect clouds
to push into eastern WI, bringing MVFR ceilings to MTW, GRB and
ATW. Flurries will also be possible. Elsewhere, MVFR ceilings are
expected to develop overnight as flow becomes southeast and the
low levels moisten up. Once the clouds develop, it will be tough
to get rid of them on Saturday. Even if the lower clouds do break
up some, mid and high clouds will be pushing across the area, so
not much sunshine is expected.