Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/23/19
AREA FORECAST DISCUSSION
National Weather Service Albany NY
1021 PM EDT Fri Mar 22 2019
.SYNOPSIS...
Cold, cyclonic flow around low pressure in the Gulf of Maine,
will bring rain, snow and gusty winds into Saturday morning. It
will remain cold and blustery for Saturday afternoon, before
fair weather and milder temperatures return for Sunday.
&&
.NEAR TERM /THROUGH SATURDAY/...
Winter Storm Warning remains in effect for the western/southern
Adirondacks, western Mohawk Valley, eastern Catskills,
Helderbergs, northern Taconics, northern Berkshires and southern
Greens through Saturday morning...
Winter Weather Advisory remains in effect for the
central/eastern Mohawk Valley, Capital District, Lake George
Saratoga Region, central Taconics, southern Berkshires and
northern Litchfield Hills through Saturday morning...
As of 1015 PM EDT, cloud tops continue to cool across the
forecast area this evening as the main upper level low pivots
around the other upper low moving eastward. This intrusion of
cooler air should allow for rain showers to change over to snow
in most locations overnight. The 00Z Albany upper air sounding
showed the freezing level around 1100 ft.
Prev Disc...
As of 740 PM EDT, latest GOES16 water vapor imagery
shows upper level low shifting mainly east across NJ/southern
NY. This is resulting in snow shower activity transitioning to
an upslope snow as the flow turns out of the west and becomes
blocked. This is already apparent in radar imagery, especially
across the Taconics. Rain showers currently in the valleys
should transition over to snow tonight as boundary layer temps
cool as well. So have freshened up the hourly temps and pops to
reflect recent trends.
Prev Disc...
As of 434 PM EDT...Radar shows precipitation falling over most
of the forecast area. Latest RAP analysis shows upper level low
along the NY/PA border near the southern tier of NY. This upper
low is forecast to move east southeast tonight and pass across
the far southern part of our forecast area before merging with
another upper level low now over the Gulf of Maine. As it passes
by, the Albany Forecast Area will be in a favored area for
precipitation, sort of a comma head. As temperatures fall
overnight, any rain will change to snow and all areas should see
at least a coating of snow overnight.
Current temperatures range from freezing or below at 2000` and
above, to the low to mid 30s in the hill towns to the low 40s
in the mid Hudson Valley. Web cams and METARS show that snow is
falling at elevations above 1000` and a mix of rain and snow
below that. We`ve seen a few wet snowflakes at times mixed in
with the rain here at the office.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
As the second upper level disturbance moves in from the west
and merges with the low over the Gulf of Maine, colder air
aloft will advect in. We are expecting a complete change to
snow to occur during the evening hours, with change from rain to
snow occurring more gradually and later for elevations below
500 ft. Snow-liquid ratios will start to increase as the entire
column cools. Last places to change will be right along Hudson
River which are near sea level and may not change over until
around midnight.
Widespread snow will then occur due to deformation/wrap-around
moisture from the large gyre centered over eastern New England.
With NW flow strengthening, upslope enhancement with occasional
moderate snow intensity will occur across the NW Adirondacks,
northern Catskills, and N-S spine of the Taconics and western
New England hills/mountains. Forecast Froude numbers from the
NAM tonight into early Saturday morning are between 0.3 to 0.7,
which implies slightly blocked to blocked flow. So we expected
the most accumulating snowfall along and just west of the
southern Greens, Berkshires, Litchfield Hills and Taconics. The
snow will gradually taper off to scattered snow showers Saturday
morning, as the strong low pressure system moves into the
Canadian Maritimes and the best moisture fluxes shift east of
the region. Additional snowfall expected to be highly elevation
dependent, with 6-12+ inches above 1500 ft, 3-6 inches below
500-1500 ft, and a coating to 3 inches below 500 ft.
After the snow ends, it will be blustery and cold through the
rest of the day Saturday. Wind gusts of 30-40 mph will be
common across the region, but we are expecting gusts to be just
below Advisory criteria due to relatively shallow mixing heights
around 900mb based on forecast soundings. We will continue to
monitor trends and mention threat in the HWO. Highs on Saturday
from around freezing in the hill towns to the mid 40s in the mid
Hudson Valley, and the windy conditions will make it feel
colder.
Cold and breezy, but dry conditions expected on Saturday night.
NW Winds will not be as strong, but a breeze will persist due
to high pressure moving eastward across the Carolinas. Lows
Saturday night in the teens and 20s. A warming trend is expected
for Sunday with continued dry conditions. highs on Sunday from
the 40s in the hill towns to the 50s in the Mid Hudson Valley.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
Expect below normal temperatures for the first half of the final
week of March as an arctic cold front on Monday ushers in
temperatures 10-15 degrees normal through Wednesday. Temperatures
should rebound back near to and even a bit milder than normal
heading towards the weekend. Read on for details.
The aforementioned arctic cold front will be pushing southeastward
from the St. Lawrence River Valley into eastern NY and western New
England during the morning hours on Monday. Surface winds look to
shift to the northwest early in the day denoting the surface frontal
boundary with the associated surface low still far to our west in
the Ohio Valley. Moisture along the actual surface frontal boundary
looks fairly limited so we only expect linger rain (valley) and snow
(elevation) showers from the overnight to continue progressing south
and east from the Capital District into the mid-Hudson Valley Monday
morning. As the surface low travels eastward from the Ohio Valley
into the mid-Atlantic on Monday, an enhanced period of precipitation
looks possible but all of the global guidance members keep that wave
well to our south in the mid-Atlantic. In fact, there is good model
consensus showing an abundance of dry air at 700mb arriving in the
wake of the frontal passage which should lead to clearing skies and
deepening mixing heights through the day Monday. BUKFIT profiles
support this with breezy conditions developing within the deep layer
northwest flow resulting in continued cold air advection. Such a set-
up likely will keep high temperatures below normal, only reaching
into the 30s to low 40s.
Winds shift northerly Monday night denoting the arrival of the true
Canadian air mass into the Northeast. 850mb isotherms fall to
-10C to -18C by 12z Tuesday (2-3 standard deviations below normal
per the GEFS) and with breezy winds continuing overnight, expect a
chilly night with lows falling into the teens and 20s (single digits
for the Adirondacks and Greens). Tuesday will remain chilly as the
Northeast remains on the west side of the large scale ~1035mb high
pressure responsible for this air mass change which will keep
northerly flow in play. Tuesday should be the coolest day of the
week with high temperatures 10-15 degrees below normal, only
climbing into the 30s for most areas. Luckily, skies should be
mostly sunny so the strengthening March sun angle should make it
feel a bit warmer.
Our large scale high pressure should move overhead Tuesday night
into Wednesday. Increasing subsidence and dew points very low in the
single digits should lead to calm winds and clear skies resulting in
nearly ideal radiational cooling conditions Tuesday night. Low
temperatures should once again fall much below normal, even cooler
than Monday night with calm winds, reaching the low - mid teens
(single digits again Adirondacks/Greens) by Wednesday morning.
Another sunny day expected Wednesday as high pressure is positioned
over the Northeast. As it heads eastward during the day, we should
see return southwesterly flow develop allowing high temperatures to
turn a bit milder reaching into the 30s and 40s. However, this is
still 5-10 degrees below normal but again the March sun should help
make it feel warmer.
Thursday - Friday turns warmer into the 50s to potentially near 60
as high pressure moves into eastern New England and southwesterly
flow remains in place over eastern NY and western New England. We`ll
have to monitor a few systems from the Midwest that looks to travel
northeastward but high pressure firmly in place off the New England
coast could steer them to our north and west until possibly the
weekend. Keep tuned to future updates for details.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
Variable flying conditions will continue overnight into Saturday
as an upper level low moves across the region. A mix of rain and
snow showers will be possible. For KPSF, upslope conditions and
cooler temperatures will result in mostly snow that is expected
to continue into the overnight period. KALB should see evening
rain showers change over to snow showers overnight with snow
showers also impacting KGFL. A brief period of rain showers will
be possible at KPOU this evening. So IFR conditions are
expected to linger for KPSF, with MVFR/VFR conditions at KGFL-
KALB with mostly VFR conditions at KPOU.
Precipitation is expected to end across the entire region Saturday
morning within a couple hours of sunrise. Otherwise, brisk
northwest winds will continue with VFR conditions for Hudson Valley
TAF locations and improving to MVFR at KPSF.
Outlook...
Saturday Night: Low Operational Impact. Breezy NO SIG WX.
Sunday: No Operational Impact. NO SIG WX.
Sunday Night: Low Operational Impact. Slight Chance of RA...SN.
Monday: Moderate Operational Impact. Chance of SHRA...SHSN.
Monday Night: No Operational Impact. NO SIG WX.
Tuesday: No Operational Impact. NO SIG WX.
Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: No Operational Impact. NO SIG WX.
&&
.FIRE WEATHER...
A coastal storm will bring rain and snow to the region tonight
through early Saturday. High terrain areas will see a moderate
to heavy snow accumulation, which will add to the snowpack
already in place. This will help limit fire weather concerns for
the time being across the region. Gusty northwest winds of
25-35 MPH are forecast tonight and Saturday.
&&
.HYDROLOGY...
No hydrologic issues are anticipated for the next week.
After rain and snow today into Saturday morning, high pressure
is expected to bring mainly dry conditions for the upcoming
week. Forecast Precipitation for the next week after Saturday is
less than a tenth of an inch. Minor rises are forecast from
today`s rain and snow. Diurnal snow melt will lead to minor
changes in river stages during the upcoming week.
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...Winter Weather Advisory until noon EDT Saturday for CTZ001.
NY...Winter Weather Advisory until noon EDT Saturday for NYZ039>041-
043-048>050-052-053-061-083-084.
Winter Storm Warning until noon EDT Saturday for NYZ032-033-
038-042-047-051-054-058-063-082.
MA...Winter Weather Advisory until noon EDT Saturday for MAZ025.
Winter Storm Warning until noon EDT Saturday for MAZ001.
VT...Winter Storm Warning until noon EDT Saturday for VTZ013-014.
&&
$$
SYNOPSIS...SND
NEAR TERM...SND/JLV
SHORT TERM...SND/JPV
LONG TERM...Speciale
AVIATION...BGM/JLV
FIRE WEATHER...SND
HYDROLOGY...SND
AREA FORECAST DISCUSSION
National Weather Service Binghamton NY
938 PM EDT Fri Mar 22 2019
.SYNOPSIS...
A complex coastal storm will bring gusty winds and periods of
snow through tonight. Snow accumulations will vary greatly
across the area, with the highest amounts expected north and
northeast of Binghamton tonight. Turning much colder tonight and
Saturday. Then, milder and mostly sunny weather for Sunday.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
With the evening updates, we incorporated some elements of
latest HRRR and RAP model runs. This lowered snowfall totals a
bit from Ithaca to Syracuse on the western edge. The general
area of snow has been slow to pivot southwestward this evening
into these areas. However, the snow is still expected to
quickly exit northeast by sunrise which limits the time of
steadier snow. Otherwise, forecast remains on track.
350 PM Update...Round two of our very complex late winter storm
is now starting. Two upper level low pressure systems, one near
Boston and one near Buffalo will merge tonight...wrapping
Atlantic moisture back into parts of our area from the north.
Latest radar trends show snow (some rain in the valleys)
wrapping back down near Utica, Rome, Syracuse and Oneonta.
Meanwhile, more convective type showers of snow, snow pellets
and rain are streaking across our west, central and southern
zones at this time associated with the western upper low.
Later on this evening the the latest mesoscale models still
indicate a solid period of wrap around snow enveloping much of
Central NY and even into the northern tier of PA. Temperatures
fall quickly once the aforementioned upper level low slides by
to our east after about 7-8 PM. Snow to liquid ratios increase
to around 15:1 overnight and with the gusty northwest winds
there will likely be areas of blowing and drift snow...mainly
over the higher elevations. Overall, not too much change in the
forecast snow amounts this evening and tonight. Winter storm
warning remains in place for all areas, except northern Wayne
county (PA) where a winter weather advisory is now in effect.
Winter weather advisories also remain in place for the same
locations. Lower confidence in reaching warning criteria for
much of Oneida county due to forecast downsloping and
shadowing...but could still see some higher amounts across the
southern portion of the county so will continue the warning for
now. Decided to just go with an advisory for southern Cayuga
county, although do believe much of the county will see a solid
5-6 inches....but confidence in any 7 inch plus amounts was not
quite high enough at this time. The snow quickly tapers off to
snow showers and flurries from west to east between 4-8AM
Saturday. Overnight lows will be most 20-25 degrees.
Saturday: A few lingering snow showers and flurries in the early
morning across north-central NY, especially east of I-81. Mostly
cloudy to start, but then clouds quickly decrease with it
becoming mostly sunny from west to east by afternoon. Still cold
and breezy. Northwest winds 10-20 mph, with gusts 30-35 mph
early. High temperatures reach the upper 20s to mid-30s across
central NY...and the mid-30s to lower 40s across NE PA.
Saturday night: High pressure builds overhead with warming
aloft. Winds decrease overnight, mainly less than 10 mph toward
morning. Clear skies with lows in the 20s
Previous Discussion Below
1200 PM Update...A lull in our winter storm now, and for the
next several hours as the main deformation band has weakened
and shifted over the western Catskills/Mohawk valley region.
Mostly dry for now back to the west across the southern tier of
NY, Finger Lakes and much of NE PA. The next upper level
wave/low is racing across western NY and PA, and this will bring
a renewed area of snow showers by late afternoon and early
evening. This upper level energy will also reinvigorate the
coastal low...helping it to lob additional Atlantic moisture
into our areas from the north as it becomes vertically stack,
and nearly stationary along the New England coast tonight. Made
update to PoPs, QPF, snow amounts and winter headlines. Did add
in a slight chance of thunder over our southwestern zones as
this strengthening upper level low moves through, increasing low
level lapse rates. Continue to mention blowing snow in the
forecast tonight, with wind gusts up to 40 mph. Cancelled the
winter weather advisories across much of NE PA (except still a
winter storm warning for N Wayne, and advisory for Susquehanna).
Still expecting an additional 3-7 inches in the lower elevations
of the warning area, with 5-10 inches over the higher terrain
here. Expect an additional 1-3 inches in the advisory area in
the lower elevations...with mainly 2-5 inches across the higher
terrain here. Localized higher amounts are still possible across
portions of southern Cayuga county from this second round of
snow this evening/tonight...so will need to continue to analyze
the latest data and consider upgrading this area to a warning
with the afternoon update. Will also be looking closely at
Oneida county, as the strong NW flow looks to create an area of
lower snow amounts in a downslope flow off the Tug Hill
Plateau...therefore expect a local minima of only 1-3 additional
inches from near Rome to Delta Lake, Whitesboro and Utica.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
Sunday and Sunday night:
High pressure across the Mid-Atlantic will move offshore leading to
a moderating trend thanks to southwesterly flow on the backside of
the high pressure system. Enough influence from the high looks to be
present for one more sunny day with the next cold front still in the
Great Lakes. Temperatures should rebound nicely into the 50`s,
likely a bit over blended model guidance. Clouds are expected to
increase ahead of the cold front with enough moisture and lift along
it for a few rain or snow showers toward sunrise Monday. Right now,
QPF from various ensembles is only a showing a tenth of an inch or
less of QPF. This would result in only minor snow
accumulations. Temperatures should fall back into the 30`s by
Monday morning, with 40`s in NE PA.
Monday through Tuesday night:
Behind the previously mentioned cold front some additional rain or
snow showers are possible on Monday. Temperatures could be
steady or slowly falling behind the front throughout the day
dependent on the frontal timing. Even with a stronger spring
sun angle, temperatures will struggle to get out of the 30`s on
Monday and Tuesday with strong cold air advection behind the
front. Lows Monday night look to fall into the 10`s. Less
concern is present for any lake effect given a slight easterly
component with the cold air advection. High pressure builds into
the region on Tuesday likely resulting in a sunny but cold day.
With clear skies, lows still look to be fairly chilly Tuesday
night in the 10`s to around 20. Lows both mornings may end up a
touch colder than model guidance because of snow cover in the
higher elevations of NE PA and the western Catskills.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
High pressure will be in firm control on Wednesday, bringing plenty
of sunshine and seasonable temperatures (highs in the 40s). This
high pressure system moves east of the area on Thursday, bringing
a southerly flow. At the same time, an upper level ridge will build
in over the region. This will result in warmer temperatures on
Thursday under mostly sunny skies, with highs likely getting
well into the 50s.
Friday looks to be the warmest day of this period, with highs
possibly approaching 60 degrees in spots, with mid to upper 50s
elsewhere. A slow moving cold front then looks to approach from
the west, which may bring some late day rain showers to CNY.
Given timing uncertainties with the front being this far out,
kept POPs in this area very low (less than 20 percent), as it
is certainly possible the entire day on Friday remains dry area-
wide.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
Radar mosaic imagery shows stratiform light snow/rain across
north central NY including KRME and KSYR terminals at this time.
Conditions were mainly MVFR ceiling and visibility in light
snow/rain. Radar trends shows more precipitation heading toward
these terminals and with a cooling boundary layer we expect all
rain to change to light snow. So we have tempo groups out to
06z-08z for IFR in snow with KRME seeing some IFR ceilings at
times until 03z. Farther south, at KITH, KELM and KBGM there
were mainly snow showers which was evolving from a more
convective nature from the afternoon heating to more stratiform
as the boundary layer stabilizes this evening. This will cut
down on some chop during ascent and descent. We expect mainly
MVFR ceilings with occasional MVFR to IFR in snow showers until
04z- 06z. For KAVP, we expect mainly VFR with IFR in snow
showers down to 1SM at times until about 03z.
This light snow and snow showers will taper down 04z-08z in our
NY terminals and by 03z-04z at KAVP. Then we will see an MVFR
deck at KRME, KBGM, KITH, and KAVP and a low VFR deck at KSYR
and KELM from 06z-08z until clearing works in from west to
east. The clearing and subsequent VFR conditions reaches KELM at
12z, 15z at KAVP and by 16z-18z at our other terminals (KSYR,
KRME, KBGM and KITH). After 18z, VFR.
Winds will be gusty from the west to northwest 15-18 kts w/ gusts
to 25-30 knots through the terminal forecast period.
Outlook...
Saturday night through Sunday night... Mainly VFR with ceilings
forming late Sunday night. A few rain or snow showers possible
toward sunrise Monday.
Monday... Any MVFR ceilings lifting through the day with
scattered rain or snow showers ending.
Monday night through Wednesday...Mainly VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...Winter Weather Advisory until 8 AM EDT Saturday for PAZ039-040.
NY...Winter Weather Advisory until 8 AM EDT Saturday for NYZ016-017-
025-055-056-062.
Winter Storm Warning until 8 AM EDT Saturday for NYZ009-018-
036-037-044>046-057.
&&
$$
SYNOPSIS...MJM
NEAR TERM...MJM/MWG
SHORT TERM...MWG
LONG TERM...BJG
AVIATION...DJN
Area Forecast Discussion
National Weather Service Bismarck ND
832 PM CDT Fri Mar 22 2019
.UPDATE...
Issued at 832 PM CDT Fri Mar 22 2019
Mid/high clouds continue to stream into southwest ND, with a
gradual expansion north and east overnight expected. This will
inhibit radiational cooling and reduce fog potential - however,
the James River Valley per high resolution models is still the
favored area for fog development tonight, from 04z-15z Saturday.
RAP BUFKIT sounding at Jamestown indicates fog development up
through 300feet during this time, with enough mixing developing
above this layer to prohibit any further increase in depth
overnight. Current forecast continues to look good.
UPDATE Issued at 539 PM CDT Fri Mar 22 2019
Latest water vapor imagery shows a northwest to southeast
mid/upper level ridge axis over western/central North Dakota this
evening. A clear sky continues underneath, with increasing
mid/high clouds on the back side of the ridge - over southeastern
MT/northwestern SD. These clouds will continue to shift into
southwest ND early tonight, then will fill in over portions of
western and south central late tonight. High resolution models
maintain patchy/areas of fog favoring the James River Valley 04z-
10z Saturday. The previous discussion/forecast had anticipated
this and is handled well. No changes with this update.
&&
.SHORT TERM...(This evening through Saturday)
Issued at 220 PM CDT Fri Mar 22 2019
Forecast highlights in the short term period will be continued
mild temperatures with fog potential each AM.
Currently, upper level high amplitude ridge over the Northern
Plains with sfc high pressure off to our east over the Western
Great Lakes region. Morning fog and stratus along with a cool
southeasterly low level flow has kept temperatures down several
degrees compared to yesterday. Still mild and seasonal for
mid/late March.
Ridge axis remains aloft tonight with a persistent
south/southeasterly low level flow regime. High res models in
agreement with fog development again tonight. Appears the
southwest and James River Valley have the best potential, though
last few model runs have been fluctuating. Given a steady 5-10
knot mixing wind do not expect as widespread as this morning, but
should see some fog/low stratus especially in low lying areas.
Ridge breaks down on Saturday as an embedded upper level low
moving east across the Central Rockies tonight, lifts north
towards our region on Saturday. I expect a milder day Saturday
(despite cloud cover) with warm temperatures remaining aloft and a
better warming south mixing wind (vs. southeast) in place for the
afternoon.
.LONG TERM...(Saturday night through Friday)
Issued at 220 PM CDT Fri Mar 22 2019
Ridge continues to break down Saturday night as the low spins east
into the Upper Midwest region. Still questionable regarding
precipitation amounts and placement, but overall moisture will
likely remain less than a quarter of an inch, closer to a tenth.
Precipitation type Sat night-Sunday morning dependent on surface
temperatures with a warm layer aloft. Latest model blend put
sleet/freezing rain across my eastern counties, which BUFKIT
analysis would support so will leave this be. Enough uncertainty
for this and lower QPF for these areas that will leave mentioning
this out of the HWO with this forecast issuance. Details should
become more clear over the next couple of forecast cycles. A rain
to snow changeover from north to south expected Sun-Sun night.
Cooler air will filter south over the later half of the weekend
and into early next week, with highs in the 30s and overnight lows
in the teens and 20s to help keep the spring snow melt in check.
Broad ridging/quasi-zonal flow develops Tuesday and Wednesday
bringing a return to milder temperatures and dry weather. This
will then be followed by another potential precipitation maker
Thursday- Friday, though much uncertainty with this period
regarding track of systems and QPF. There is decent consensus
that after the Thu-Fri time period a shot of much colder air will
move south out of Canada into the Dakotas for the following
weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 539 PM CDT Fri Mar 22 2019
Clouds increasing across the terminals this taf period, with MVFR
cigs expected at KDIK from 12z onward, then IFR cigs develop late
in the taf period. KJMS will be the terminal most prone to fog
tonight resulting in LIFR visibilities and MVFR cigs from 05z-13z
Saturday. KISN/KMOT will also see ceilings deteriorate to MVFR
conditions beginning around 21z Saturday.
&&
.HYDROLOGY...
Issued at 245 PM CDT Thu Mar 21 2019
Flood warnings are in effect for the Missouri River and the Little
Muddy Rivers in the Williston area. The Little Muddy is expected
to fall below flood stage on Saturday, while the Missouri River is
expected to remain above flood stage into next week.
Flood warnings are also in effect for the Knife River near
Manning and near Hazen, as well as for Spring Creek at Zap. Beulah
is also affected by the Knife River and Spring Creek. River and
creek levels here are forecast to fall below flood stage either
daytime Saturday or Saturday night.
Snowmelt continues, especially for the western half of the state.
Be on the lookout for some rising levels in other rivers and
creeks in western North Dakota this weekend, especially in western
and south central North Dakota. The Heart and Cannonball Rivers
and Cedar Creek and their tributaries may see continued rises this
weekend.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...NH
LONG TERM...NH
AVIATION...KS
HYDROLOGY...JV
Area Forecast Discussion
National Weather Service Denver/Boulder CO
930 PM MDT Fri Mar 22 2019
.UPDATE...
Issued at 930 PM MDT Fri Mar 22 2019
Other than the large landspout on the low level shear axis near
Eaton earlier this evening, the forecast is going about according
to plan. Temperatures have cooled to the mid to upper 30s in the
areas with heavier precipitation, but will only cool slowly from
this point on as there isn`t really any low level cold advection.
The focus has already shifted east of the mountains, though the
back edge will probably be messy through the middle of the night
as the low level winds are trying to anticyclone right now and
will probably be wobbling around until there`s a more solid
northwesterly flow later tonight. At that point, Denver will start
to get sheltered while showers with decreasing intensity continue
over much of the northeast plains. This will also shift the
mountains into more of a light orographic snow regime, but helped
a bit by the continuing mid level instability. All of this is
pretty well covered. Changes this evening included slowing the
development of widespread rain over the eastern portion of the
plains where this is only starting to fill in now. We may also be
a couple hours fast moving the rain/snow out of Denver as the HRRR
runs have this happening in the 10z-14z time range now from SW
Denver to DIA. This also seems to match the slower eastward spread
of the rain this evening with the trough axis still back around
Ft Morgan-Limon. The handling of the snow level and possible
accumulations mainly in Elbert county and right at the Wyoming
border still looks good.
&&
.SHORT TERM...(This evening through Saturday)
Issued at 325 PM MDT Fri Mar 22 2019
Latest satellite and radar imagery shows the convection developing,
although the majority of this so far has been to our south. It
will continue to advect northward and fill in through the evening
hours, as moderate QG ascent combines with the unstable airmass.
The track of the upper level low, from the Colorado/New Mexico
border into east central Colorado tonight, would suggest a period
of upslope. However, along the Front Range, we expect a rather
quick transition to a slight downslope NNW component by late
evening. Along this wind shift and mid level convergence, we will
see strong frontogenesis, and an enhanced band of precipitation
with higher rates. That band should shift slowly east to just east
of the I-25 Corridor late this evening, and then possibly stall
overnight as low pressure system deepens, effectively keeping a
prolonged period of frontogenesis and enhanced precipitation over
our plains.
As a result, we will continue to push up our QPF numbers for just
east of the I-25 Corridor. At the same time, the heavier
precipitation will likely drive down snow levels a little more,
especially over the Palmer Divide where a deep northerly upslope
component develops. The combination of these two factors will
likely lead to a quicker changeover and thus more snow
accumulation. We have boosted amounts toward the middle range of
the short term guidance, relying heavily on HRRR variable method
snow accumulation. This is normally much better than a typical
10:1 ratio in these marginal temperature events where there is
considerable melting. Will still have to watch the latest trends
closely as just a degree or two could make a significant
difference in snow amounts and accumulations. Right now, we expect
the brunt of the snow to occur overnight, with mostly slushy
conditions, so impacts shouldn`t be too much for areas from
Douglas into Elbert/northern Lincoln county. Best estimates for
those areas would be 1-4 inches. Around Denver, look for mostly
rain although a few wet snowflakes will likely occur over the
southeastern sections of town later tonight, perhaps just enough
for a dusting.
In the mountains, snow showers, some heavy, early this evening
will gradually decrease later in the evening and overnight as
airmass stabilizes.
On Saturday, the morning rain/snow east of the I-25 corridor
plains will gradually diminish to showers as the storm system
pulls away. A few snow showers will linger in the mountains with
enough orographics and shallow moisture. Temperatures will be
slightly cooler, but a little downslope will help push readings to
just shy of normal levels along the I-25 Corridor. It will be a
little breezy in the post trough airmass as well.
.LONG TERM...(Saturday night through Friday)
Issued at 325 PM MDT Fri Mar 22 2019
Moisture will remain over the mountains Saturday night and Sunday
as westerly flow aloft will continue across the state. This will
keep light scattered snow showers going west of the Continental
Divide. The flow aloft will not be particularly strong, but
stability will be low, which will allow the orographic shower
activity to continue. By Sunday afternoon and evening, heights
will be rising and flow aloft is forecast to turn more
northwesterly. However, we will be under the left exit region of
a broad upper jet, while the airmass remains marginally unstable.
The result will be a chance of showers moving out over northeast
Colorado through the afternoon and evening. Temperatures will be
around seasonal normals.
After Sunday evening, heights over Colorado will rise in earnest
with dry and warmer conditions across the forecast area through
much of the week. Wednesday looks to be the warmest day of the
week with highs into the lower 70s across the plains. The upper
ridge is forecast to be moving eastward on Thursday with flow over
Colorado becoming southwesterly. Friday and Saturday look cooler
and unsettled as a broad upper trough will be in place over the
state. Mountain areas will pick up some more light snow while the
plains see a mixture of rain and snow, depending on the
temperatures and the time of day or night.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 930 PM MDT Fri Mar 22 2019
Rain, occasionally mixed with snow, will continue through 08z and
then gradually diminish, ending between 10 and 14z. No snow
accumulation is expected on paved surfaces in the Denver area.
The rain will produce areas of MVFR conditions but only localized
IFR through about 14z. After that, higher ceilings are expected
though instrument approaches to KDEN may still be needed until
19z. North winds gusting in the 20-30 knot range at KDEN/KAPA will
diminish to 10-15 knots by 12z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Gimmestad
SHORT TERM...Barjenbruch
LONG TERM...Dankers
AVIATION...Gimmestad
Area Forecast Discussion
National Weather Service Columbia SC
823 PM EDT Fri Mar 22 2019
.SYNOPSIS...
A pressure ridge extending through the Mississippi River Valley
tonight will be in the forecast area Saturday and off the coast
Sunday. It will remain dry through Sunday. A cold front will
approach Monday and be in the area Monday night. Showers and a
few thunderstorms may occur.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Updates to the forecast this evening are pretty modest. Temps
are falling a little slower than previous forecast, so I have
adjusted them upward by a degree or two, but nothing
significant. Winds are coming down gradually as we are now past
sunset, and the latest HRRR continues the trend of bringing the
winds to near calm over the north after 09Z, so the patchy frost
still looks possible over Chesterfield and Lancaster counties
toward sunrise.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
The dry surface ridge is forecast to extend through the
forecast area Saturday and Saturday night. It will remain dry.
Wind will be light with the ridge axis in the region. The ridge
will be off the coast Sunday and Sunday night. Warming will
occur in the southerly flow on the backside of the offshore
high. There will also be a moisture increase in the flow and
ahead of broad upper troughing. Based on the initial dryness and
weak lift showers will likely hold off through Sunday night.
The models show increased moisture Monday ahead of a cold front
and increased upper troughing. The guidance consensus supports
pops around 50 percent Monday. There may be enough instability
for thunderstorms. The GFS has weak instability with surface-
based LI values -2 to -4. Followed the guidance consensus for
the temperature forecast.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
The models show the cold front in the forecast area Monday
night supporting showers and possible thunderstorms. The front
is forecast to sink south of the area Tuesday. The front in the
region indicates a continued chance of showers. The GFS and
ECMWF display dry ridging in the area Wednesday through Friday.
Below normal temperatures will occur behind the cold front for
Tuesday and Wednesday. The guidance consensus supports lows in
the 30s Tuesday night and Wednesday night. It should be warmer
Thursday and Friday because of air mass modification.
&&
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
High confidence in VFR conditions for the next 24 hours.
Northwesterly flow aloft and surface high pressure building
into the area from the west will promote dry weather and clear
skies through Saturday. Westerly surface winds around 10 to 15
knots with gusts to around 20 knots will diminish shortly after
sunset this evening. Light and variable winds after 06z
continuing through Saturday. No fog tonight due to mixing and
dry air advection. A few high clouds possible on Saturday but
mainly clear.
EXTENDED AVIATION OUTLOOK...Restrictions possible late Sunday
night through Monday as a low pressure system moves into the
region.
&&
.FIRE WEATHER...
Minimum RH will be around 20 percent Saturday, although winds
will be light and variable.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
&&
$$
SYNOPSIS...99
NEAR TERM...99
SHORT TERM...99
LONG TERM...99
AVIATION...99
FIRE WEATHER...
Area Forecast Discussion
National Weather Service Cheyenne WY
555 PM MDT Fri Mar 22 2019
.SHORT TERM...(Tonight - Sunday)
Issued at 304 PM MDT Fri Mar 22 2019
The main focus over the next 24-36 hours will be the potential for
heavy rain and flash flooding across portions of southeast Wyoming
and the western Nebraska Panhandle. The latest GOES-16 Water Vapor
satellite loop indicates a vigorous upper-level low lifting north-
east across the 4 Corners into CO late this afternoon. Substantial
dynamic support in advance of this feature has already contributed
to widespread showers across the region, w/ snow levels roughly 7k
feet or so. Regional radar data is showing convection now starting
to develop over eastern CO, which is no surprise given MUCAPE near
500 J/kg along and south of the I-80 corridor. This, combined with
PWATs in excess of 0.5 inch & deep saturation on forecast sounding
data, will support a heavy rain threat this evening/overnight over
portions of the area.
Ultimately, the biggest question is exactly where we will see some
of the heavier precipitation develop. High-res guidance is leaning
strongly toward slow-moving, training thunderstorms along a north-
south oriented band, anywhere from the Laramie Range eastward into
the Kimball/Scottsbluff areas. This may become more clear over the
next few hours as the inverted trough sets up, as this convergence
will be important to precipitation intensity. Good news & bad news
as snow pack has been worked in with recent warmth, but the ground
is saturated with little room for additional water input. We could
very well need some Flash Flood Warnings this evening, so we opted
to make no changes to the inherited Areal Flood Watch. One concern
for tonight depending on where the heavier bands set up, as recent
HRRR runs did suggest heavier showers over the I-80 Summit. Precip
will be in the form of snow at elevations above 7000 feet, so snow
could pile up quickly and cause travel problems. Confidence is far
too low to issue a Winter Weather Advisory at the moment, but with
conditional potential for up to 6 inches of snow we have issued an
SPS to heighten awareness to travelers heading that direction.
Wrap-around precipitation is expected to persist for far southeast
WY and the southern NE Panhandle through at least mid-day Saturday
but convective potential will not be as high as today. This may be
problematic for flooding concerns.
.LONG TERM...(Monday - Friday)
Issued at 330 AM MDT Fri Mar 22 2019
We stay in an active pattern for next week as a few shortwaves
move through the area. Starting off Sunday night...we have a
stalled out frontal system laying across the Nebraska Panhandle
up into Converse and Niobrara Counties. Clipper shortwave rides
over this front with showers mainly along and north of Douglas to
Torrington to Sidney. GFS 700mb temperatures down near -4C and
given its a night time event...have predominantly snow in the
forecast up there.
The front lifts northeast as a mid level ridge builds in for
Monday afternoon. Should be dry most of Monday. Ridge stays with
us through Wednesday before axis shifts east.
Next low pressure system set for Thursday. GFS depicting this as a
pretty cold system with 700mb temperatures down near -10 to -13C.
ECMWF keeps system further north over Montana. So we will need to
continue monitoring this system. For now...kept precip mainly
liquid with this system.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday afternoon)
Issued at 555 PM MDT Fri Mar 22 2019
A challenging first 6 hours of this TAF issuance with convective
precipitation fairly widespread along and east of I-25. Localized
moderate to heavy rainfall may lower conditions to IFR. Included
VCTS for KCYS through 02Z. Light snow will continue at KLAR, with
transition to snow by 04Z at KCYS. Stratiform rain will prevail for
the plains from late tonight into Saturday with IFR-LIFR conditions.
With the exception of KRWL with W-SW winds 10-15 kt, winds will be NW
10-20 kt at KLAR and KCYS, and E-SE 10-20 kt becoming N-NE 5-10 kt
for the NE Panhandle terminals.
&&
.FIRE WEATHER...
Issued at 330 AM MDT Fri Mar 22 2019
Mid and high level clouds have moved in ahead of showers and
afternoon thunderstorms expected later today. Thunderstorms will
be associated with areas of heavy rain and a Flood Watch has been
issued for areas east of the Laramie Range in anticipation of the
heavy rain and rain on snow flood concerns. The system, and
accompanied low fire weather concerns, will take the weekend to
move east, but a ridge of high pressure will move into the region
by Monday with humidities crashing into the low to mid twenties.
The next system won`t move in until the end of the week next
week.
&&
.HYDROLOGY...
Issued at 304 PM MDT Fri Mar 22 2019
Major flooding continues to be observed at downstream gages of the
White & Niobrara rivers. As such, high water levels likely persist
across Dawes county in Nebraska. Limited snow pack remains, but up
to one half inch of rainfall over the next 24 hours should promote
continued flooding. A Flood Warning remains in effect until Monday
morning for Dawes county, with Flood Advisories for adjacent zones
as well as Banner county where some low water crossings are seeing
some impacts. An Areal Flood Watch is in effect thru Saturday, for
areas roughly along/east of I-25. Widespread rain is expected this
evening/overnight, and through much of Saturday. Rain amounts one-
half to one inch may accelerate snowmelt in some areas, or perhaps
result in rapid runoff due to saturated ground. There is potential
for localized flash flooding this evening. Further west across the
mountains, a favorable thaw cycle continues with high temperatures
in the 40s and lows below freezing. A few gages, including the Med
Bow River at Elk Mountain, indicate a diurnal cycle with a gradual
climb toward Action Stage. However, this trend has slowed a bit in
the last 24 hours, so no immediate flooding concerns are indicated
at this time.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Flood Watch through Saturday afternoon for WYZ102-107-108-118-
119.
NE...Flood Watch through Saturday afternoon for NEZ002-003-019-020-
054-095-096.
&&
$$
SHORT TERM...CLH
LONG TERM...GCC
AVIATION...MAJ
FIRE WEATHER...AB
HYDROLOGY...CLH
Area Forecast Discussion
National Weather Service Dodge City KS
640 PM CDT Fri Mar 22 2019
...Updated Aviation Discussion...
.SHORT TERM...(This evening through Saturday)
Issued at 353 PM CDT Fri Mar 22 2019
The Texas Panhandle severe weather event was starting to unfold as
of 2015Z, as formidable convection was developing in a region of
strong boundary layer convergence along the NM border with the TX
Panhandle. The northern edge of the 600+ J/kg SBCAPE was still
confined to the northern TX Panhandle without much in the way of
northern advancement, as surface winds in the OK Panhandle and far
southwest KS were not supportive of good moist advection from the TX
Panhandle. The aggressive development of convection will now likely
keep the upper 40s/near 50F dewpoints just south of far southwest
KS, but it will be close. The best window for any strong/severe
convection impinging on the Elkhart-Liberal corridor will be 23Z to
02Z time frame. The HRRR model runs today have been fairly
consistent in an upscale growth of convection into a quasi-linear
structure from the eastern Panhandles up into southwest KS, mainly
south of a Sublette to Bucklin line. The main threat from any of
these storms would be marginally severe wind, but even that
probability looks quite low. The main interest will be locally heavy
rainfall, as some locations may see upwards of an inch of new rain
(in combination with today`s showery activity) when all is said and
done.
The synoptic dry intrusion will work northeast quickly late tonight,
with precipitation pushing north and east of our forecast area by
06Z (the exception being Barber and perhaps Pratt County). The upper
low lifting into east central CO/northwest KS will be occluding fast
late tonight/early Saturday. As the low fills, it will track slowly
east along the I-70 corridor, so we will need to keep some 30-40
POPs up along mainly I-70 for additional showers and perhaps an
isolated thunderstorm or two near the upper low center, given how
cold aloft it will be (-22C at 500mb). It will not take much
insolation at all to destabilize the lower/mid troposphere, yielding
a few hundred J/kg of SBCAPE. The low will finally pull away
Saturday Night with downslope west-northwesterly flow in its wake.
.LONG TERM...(Saturday night through Friday)
Issued at 353 PM CDT Fri Mar 22 2019
The next system in line for Monday is looking less impressive, as
the shortwave trough will lose much of its integrity as it blends
into the confluent mid/upper flow pattern that will still remain to
some degree across the Central Plains. Nevertheless, we will
maintain some Chance POPs late Sunday Night into early Monday for an
expected very low precipitation amount forecast. Much larger scale
ridging will build across the Rockies Monday and move quickly across
the central CONUS Tuesday with southwest flow aloft developing
across the Rockies and adjacent High Plains Wednesday. As a result,
much warmer temperatures will occur in the lower troposphere. The
west-southwest downslope will lead to a rather pronounced leeside
trough, so south winds will be increasing by Wednesday. Low level
moisture will be on the increase as well, with some lower to perhaps
mid 50s dewpoints surging back north into KS.
There may be an isolated thunderstorm or two late
Wednesday/Wednesday evening, but there will not be much in the way
of upper level support for sustained deep, moist convection as the
primary trough will still remain well off to the west across
California and Nevada. This trough will advance east, closer to the
Central Plains by late Thursday, and a rather sharp cold front is
shown by the ECMWF to come down about this same time.
Thursday/Thursday Night would be the better opportunity for
strong/severe thunderstorms somewhere across the Central Plains, but
since this storm system is still 6 days away, that is all we will
really say about that. Both Wednesday and Thursday look quite warm
with upper 70s to even 80 or 81F possible (especially Thursday south
of the Arkansas River to the OK border).
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 631 PM CDT Fri Mar 22 2019
Rainshowers along with scattered thunderstorms can be expected
across southwest Kansas through midnight as an upper level low
slowly moves across the West Central High Plains. MVFR
visibilities and ceilings will be possible in and near these
thunderstorms early tonight from the steadier and heavier
showers. As the precipitation tapers off from west to east after
midnight the lower levels will saturate and MVFR to IFR ceilings
are forecast to develop. Areas of 1-3sm fog will also be possible
at times around daybreak. These low ceilings and visibilities
will improve between 12z and 18z Saturday with the exception of
the Hays area where some low clouds may linger into the early
afternoon. The winds outside the thunderstorms overnight will be
primarily southeast at 10 to 15 knots.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 42 61 38 67 / 100 20 0 0
GCK 41 58 37 65 / 100 20 0 0
EHA 36 64 37 66 / 100 0 0 10
LBL 41 64 39 67 / 100 0 10 0
HYS 43 55 39 62 / 90 60 20 0
P28 45 64 40 68 / 90 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Umscheid
AVIATION...Burgert
Area Forecast Discussion
National Weather Service Duluth MN
1016 PM CDT Fri Mar 22 2019
.SHORT TERM...(This evening through Saturday)
Issued at 258 PM CDT Fri Mar 22 2019
Very quiet conditions through the day Saturday as high pressure
dominates the region and upper-level ridging builds over the
northern Great Plains. A large area of high pressure, currently
centered over central Ontario, will translate southward over the
Northland this evening and overnight. Clear skies and light winds
with the high overhead will enhance radiational cooling. Low
temperatures tonight will fall into the lower teens over north-
central Wisconsin to near 20 over far northern Minnesota. There is
some uncertainty about the potential for fog development over
northwest Wisconsin, where the high pressure center and weakest
winds will be most likely. The high-res models are leaning towards
higher dew point depressions, although the RAP soundings suggest at
least some patchy fog. I went ahead and added some patchy fog to the
forecast, but kept the coverage very isolated.
The high pressure will continue to dive southward into the Ohio
River valley late tonight and Saturday morning, allowing southerly
return flow and warm air advection to develop across the Northland.
Temperatures are forecast to be quite a bit warmer Saturday compared
to today, with highs in the lower to mid 50s. We did increase the
wind speeds for Saturday as stronger 850 mb level winds builds into
the northeastern portions of the forecast area. With boundary layer
mixing progged to be around 900 mb, there should be enough momentum
transport to mix down these winds to the surface. Gusts between 10
to 20 mph will be possible, especially in the Arrowhead where the
strongest flow aloft will be.
.LONG TERM...(Saturday night through Friday)
Issued at 258 PM CDT Fri Mar 22 2019
A cold front will move through the area Saturday night, but a
storm track through the lower Great Lakes will tie up a majority
of the available moisture, making precipitation in the Northland
light and variable. There could be some trace amounts of freezing
drizzle up near the international border and along the north shore
of Lake Superior, but most of the precipitation that falls on
Sunday will start as rain and transition to snow Sunday evening.
High pressure will settle in after the cold front, bringing a
cool start to next week, with high temperatures reaching the
upper 30`s with overnight lows in the teens for a majority of the
forecast area.
The next significant system will take aim at the area Thursday and
into Friday. There is still some disagreement on the exact storm
track between the models, but most areas can expect to receive
some rain before it transitions to snow during the overnight
hours. Forecasted PW values are low with this system, but given
the gradual warming trend, and the significant snowpack in some
areas there will continue to be a risk of river flooding.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 645 PM CDT Fri Mar 22 2019
Quiet conditions expected through Saturday as high pressure sits
over the Northland this evening. Calm winds and clear skies
overnight will bring a slight chance for patchy fog in the early
morning, but confidence is not high on it being significant or
widespread. Patchy MVFR conditions are possible at KHIB, KBRD, and
KHYR. Otherwise, VFR conditions expected.
&&
.MARINE...
Issued at 1015 PM CDT Fri Mar 22 2019
Fairly quiet over the waters this evening. Winds pick up on
Saturday from the southwest and will build waves along the North
Shore. A front drops down from the north on Sunday morning and
will pick up wind speeds and build waves along the North Shore
again except this time winds will be from the northeast.
&&
.HYDROLOGY...
Issued at 258 PM CDT Fri Mar 22 2019
Regional snowmelt continues, with temperatures above freezing
through the forecast period. This will lead to area river levels
increasing. The latest river stage forecasts indicate generally
rising trends in the river levels, with the Ft. Ripley forecast
point along the Mississippi River rising to the bankfull stage
during the day Saturday. The forecast is to keep the river level
there in the bankfull stage at least through mid-week. There is a
chance for precipitation mid- to late-week as well, which could
contribute to additional water rise.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 20 50 29 36 / 0 0 0 20
INL 18 53 24 34 / 0 0 10 10
BRD 18 53 28 42 / 0 0 0 20
HYR 15 52 27 41 / 0 0 0 10
ASX 18 52 30 36 / 0 0 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&
$$
SHORT TERM...JTS
LONG TERM...TY/G2
AVIATION...Wolfe/JS
HYDROLOGY...TY/JTS
MARINE...Wolfe
Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
941 PM CDT Fri Mar 22 2019
.UPDATE...
Latest HRRR, RAP and NAM HiRes models show decreasing chances for
scattered showers and isolated thunderstorms across our area for the
rest of tonight into Saturday. Decreased PoPs by 10 percent across
the Rio Grande and southern Edwards Plateau areas and took out
thunderstorms for the most part of first forecast period.
The best energy and instability for storms to develop sits across
the Texas Panhandle this evening as an upper level system moves
across the Southern Plains.
The one thing we have added for this period into Saturday morning is
the mentioning of areas of fog across parts of the Edwards Plateau.
Latest HiRes models suggest for visibilities to drop significantly
overnight into Saturday morning between Uvalde and Rocksprings.
&&
.PREV DISCUSSION... /ISSUED 707 PM CDT Fri Mar 22 2019/
AVIATION...
Weak upward forcing overspreads our area to generate ISOLD-SCT SHRA
out west this evening, then most areas overnight into Saturday. At
KDRT, have replaced VCTS with VCSH as forcing is greatest on the
Serranias del Burro with weakening as they approach the site this
evening. Although, have maintained VCSH for all sites overnight
through Saturday, expect only short intervals of VCSH or perhaps
brief SHRA. Weak elevated instability may allow for ISOLD TSRA,
however, PROBs are too low to mention. VFR CIGs slowly lower to MVFR
overnight into Saturday as SHRA moistens the lower levels. S to SE
winds 10 to 15 KTs decrease to 7 to 12 KTs overnight into Saturday.
PREV DISCUSSION... /ISSUED 305 PM CDT Fri Mar 22 2019/
SHORT TERM (Tonight through Saturday Night)...
An upper level low is currently centered over northwest New Mexico
this afternoon, with an associated upper trough axis stretching
southward into west Texas. Considerable cloudiness continues along
the eastern slopes of the Serranias del Burro mountains in Coahuila
into the Rio Grande plains. While high clouds will continue over the
higher terrain of the Serranias, we should still see enough
insolation to help initiate convection between 20-22Z. Any convection
that manages to develop over the Serranias will then move east and
northeast toward the Rio Grande plains around 00Z. While we can`t
completely rule out an isolated strong storm or two, given persistent
cloud cover over the Rio Grande, low-level instability will be
greatly limited. Given the expected elevated nature of the storms,
hail and strong wind gusts will be the main concern if a strong storm
or two manages to develop. Some of the hi-res models manage to bring
some of the stronger convection eastward toward the San Antonio area
around midnight. At this time, our confidence in this scenario is
rather low given the stronger lift will remain north of the region.
However, later shifts will need to monitor carefully. We do expect
some showers and perhaps an isolated storm or two tonight, mainly
along and west of the I-35 corridor. Rainfall amounts will be rather
spotty, with amounts generally under 1/10 of an inch, except locally
higher with thunderstorms. Unfortunately, it appears rainfall amounts
will not have much of an impact on the D2 (severe) drought areas in
Zavala, Frio and Atascosa counties.
On Saturday, we should see enough moisture and instability to warrant
a 20-30% chance for showers across most of south central Texas. We
have also mentioned isolated thunderstorms in the forecast given the
presence of some elevated instability. Our confidence in thunderstorms
is low and if subsequent model data trends lower this this instability,
we may not see any storms at all. Again, spotty rainfall amounts are
expected with amounts generally under 1/10 of an inch. A few showers
remain possible Saturday night, but chances will remain low as the
flow aloft becomes increasingly stable.
LONG TERM (Sunday through Friday)...
For late in the weekend into early next week, we will see continued
zonal flow aloft with a trend toward upper level ridging by midweek.
We do expect a cold front to move into the region late Monday. Ahead
of the front, we should see temperatures rise into the 80s across
most areas on Monday. With moisture pooling out west Monday night, we
will mention a low chance for showers and storms along the Rio
Grande, with dry weather expected elsewhere.
Temperatures will ease back into the 70s on Tuesday and Wednesday,
with overnight lows generally in the 50s. Dry weather is also
expected midweek given dry air behind the cold front. The flow aloft
should trend a little more active by late in the upcoming work week.
With southerly flow leading to increasing moisture, we will mention
a low chance for showers and storms Thursday and Friday for areas
east of Highway 83.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 58 73 60 79 60 / 20 30 20 10 10
Austin Bergstrom Intl Airport 57 73 60 79 59 / 20 30 20 10 10
New Braunfels Muni Airport 56 73 59 79 59 / 20 30 20 10 10
Burnet Muni Airport 56 71 59 80 57 / 20 30 20 - 10
Del Rio Intl Airport 63 78 62 81 60 / 30 20 - - -
Georgetown Muni Airport 56 72 59 80 59 / 20 30 20 - 10
Hondo Muni Airport 61 74 61 82 61 / 20 30 20 10 -
San Marcos Muni Airport 57 73 59 79 59 / 20 30 20 10 10
La Grange - Fayette Regional 57 74 60 79 61 / 10 20 20 20 10
San Antonio Intl Airport 59 73 60 80 60 / 20 30 20 10 -
Stinson Muni Airport 60 74 60 81 61 / 20 30 20 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Aviation...04
Short-Term/Long-Term...17
Area Forecast Discussion
National Weather Service Marquette MI
723 PM EDT Fri Mar 22 2019
.SHORT TERM...(This evening through Saturday)
Issued at 210 PM EDT FRI MAR 22 2019
Upper Michigan sits on the eastern edge of an approaching sfc high
today as a nor`easter works its way up the Maine coastline. A
relatively strong pressure gradient allowed for breezy north winds
gusting to 30-40 mph near the lake over the east half and as high as
30 mph inland, but they`ve already begun to die down and will
continue to do so as the high moves in.
A brief burst of heavy snow over eastern Marquette county this
morning brought a quick 1-2 inches of accumulation to a few spots.
Dry low level air quickly cut that off well before noon, but some
cloudiness is lingering mainly over the east half. This will
gradually scatter out, and clear skies are expected overnight. Winds
are expected to become calm to light and variable, and radiational
cooling should be relatively efficient, so went on the low end of
guidance with teens lakeshore and mid to upper single digits inland.
Some patchy ground fog will be possible in the interior overnight,
mainly picked up in the RAP soundings, but with how dry the air is I
didn`t have enough confidence to put it in the grids.
Airmass remains dry tomorrow despite winds swinging around the the
SW and intensifying during the daytime. Clear skies and associated
WAA will allow for a quick warm-up to the upper 40s and lower 50s
except over the far east and especially near Manistique where
they may be stuck in the upper 30s. Since all the snow has long
cleared off the conifers, wouldn`t be surprised to see a few mid
to upper 50s in downslope areas.
Although sunset is now after 00Z Sunday and into the long term,
figure it`s worth mentioning that we are expecting great conditions
for Aurora viewing Saturday evening after nightfall, with the Space
Weather Prediction Center forecasting Kp numbers around 5 until 2AM
EDT (peak solar activity will unfortunately be earlier in the
afternoon). Moonrise is about 1130 EST and it was just full a couple
days ago, so best viewing will be in the couple of hours prior to
that. Find a nice dark spot away from city lights with a clear view
to your north!
.LONG TERM...(Saturday night through Friday)
Issued at 419 PM EDT FRI MAR 22 2019
Models indicate that an amplified mid/upper level ridge will persist
over western Canada into early next week resulting in downstream nw
flow through the Great Lakes. Although temps will remain generally
above normal, a clipper shortwave trough moving through on Sunday
will affect the area bringing light mixed pcpn and colder air into
Monday. As the western Canadian ridge breaks down by the middle of
next week and gets replaced by a trough, flow will become more zonal
or even southwestly into the western Great Lakes for the middle to
end of next week resulting in a trend toward above to much above
normal temps.
Sunday, Another clipper shortwave is expected that should bring
light pcpn into the area as models indicate a decent 850-700 mb fgen
response associated with the sharp cold frontal passage. With the
relatively shallow moist layer and lack of ice nuclei, mainly
dz/fzdz is expected that will transition to some leftover light snow
as the deeper cold air moves in. Temps should fall during the day
from the upper 20s north or the mid 30s south.
Mon-Fri, below normal temps Monday in a northerly flow are expected
to give way to moderation into the middle of the week as a more
zonal flow pattern develops. Temps will climb from around 30 or mid
30s Monday to the mid and upper 40s across much of the area by Wed
and likely mid 40s to mid 50s by Thu, warmest west half.
A strengthening WAA pattern along with a shortwave and low moving
into nw Ontario will bring rain shower chances into the area by Wed
night. A frontal boundary is likely to move through or near the area
by Thu night into Friday which will provide the focus for additional
pcpn. There are more signficant model differences and lower
confidence with the timing/position of this feature and any
enhancing shrtwvs moving toward Upper Michigan in the sw mid/upper
level flow.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 723 PM EDT FRI MAR 22 2019
Under the influence of dry high pres, clear skies/VFR conditions
will prevail at KIWD/KCMX/KSAW thru this fcst period. Winds will be
light/calm tonight, then become gusty to around 20kt from the w to
sw on Sat.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 210 PM EDT FRI MAR 22 2019
North winds up to 20 knots will continue to diminish across the east
half of Lake Superior this evening. Winds come back up to 30 knots
from the southwest on Sat from the tip of the Keweenaw westward.
Northeast winds up to 30 knots are expected on Sun. No gales are
expected at this time, and winds will be below 25 knots from Sunday
night onward.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...KCW
LONG TERM...JLB
AVIATION...Rolfson
MARINE...KCW
Area Forecast Discussion
National Weather Service Blacksburg VA
734 PM EDT Fri Mar 22 2019
.SYNOPSIS...
A cold front will drop south across the region this
evening into tonight. High pressure will move overhead for the
weekend, providing dry weather with winds diminishing, and
temperatures favoring the cooler side of normal.
&&
.NEAR TERM /THROUGH SATURDAY/...
As of 630 PM EDT Friday...
A cold front continues to make headway southeast across the
region as we progress into this evening, currently near the
VA/NC border. While all but a few sprinkles or isolated showers
remain of the precipitation associated with the front, very
gusty conditions will remain in association with the front.
Areas near and west of the crest of the Blue Ridge will continue
to have very gusty winds with our current Wind Advisories and
High Wind Warnings remaining in place as northwest winds behind
the front continue to remain on the strong side. Likewise, these
same winds will help maintain upslope snow showers across mainly
western Greenbrier County with some light measurable snow
expected through the evening hours, bleeding into the early
morning hours of Saturday.
As of 300 PM EDT Friday...
Winter weather advisory in effect for Western Greenbrier county into
Saturday morning.
High wind warnings and wind advisories are effect until 6 am
Saturday.
Upper level low across Pennsylvania will rotate eastward tonight
into Saturday. A cold front will drop southeast across our region
this afternoon into tonight. High pressure to our west will build
southeast into our area Saturday.
Cold air continues to filter southward into our area. However, the
coldest air will not get into the region until tonight. Thus
given the stronger March sun angle, most snowfall accumulations
will be confined to grassy surfaces or higher rates. The highest
snow accumulation will occur in western Greenbrier county where
up to 4 inches is possible and make some of the roads slushy or
snow cover tonight.
The winds have quite gusty this afternoon in the mountains and with
the cold front pushing across upgrade six counties in the southwest
mountains to high wind warning. The models have been fairly
consistent the last 2-4 days of showing a decent wind event for most
of the area. The latest HRRR and NAMNEST showed an increase in winds
along the southern Blue Ridge mountains into tonight. The strongest
winds will occur behind the cold front as cold advection gets going
with better pressure rises tonight.
As the stronger shortwave pushes in behind the cold front late this
afternoon into tonight expected scattered rain and snow showers then
a transition to upslope snow showers and snow flurries in the
mountains. If convection hold together could be an isolated
thunderstorm in the north this afternoon into evening. The Day One
convective outlook has been extended south into northeastern
portions of the forecast area. With the cold pool aloft will have to
watch for small hail and gusty winds with any strong thunderstorm.
Low temperatures tonight into Saturday morning will range from the
upper teens in the northern mountains to the lower 30s in the
piedmont. With the wind, some wind chills could drop into the single
digits in the higher ridges, with teens west of the Blue Ridge.
Saturday will be blustery with any lingering snow flurries west of
the Blue Ridge dissipating during the morning. High pressure surface
and aloft then builds over the Appalachians. High temperatures
Saturday will vary from the upper 30s in northwest mountains of
Greenbrier county in southeast West Virginia to the lower 60s in the
piedmont.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
As of 300 PM EDT Friday...
High pressure will pass overhead Saturday night and Sunday,
winds diminishing, fair weather to close out the weekend. Next
chance of precipitation is expected to arrive across the
mountains late Sunday night then spread east across the
remainder of the forecast area Monday. A cold front is forecast
to approach from the northwest Monday, associated with showers.
Models are showing a ripple of low pressure along the front, but
not as strong as previous runs. This suggests rain amounts will
not be as robust with amounts of a half inch (0.50) or less. The
upper level flow pattern looks progressive, so the entire system
may clear the area by daybreak Tuesday.
Temperatures are expected to warm ahead of the front Monday, and
this may promote enough CAPE for a rumble of thunder. Confidence
is low with respect to timing and coverage, so will omit from
the general forecast attm.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 330 PM EDT Friday...
Upper level trough over eastern Canada is forecast to retreat
next week with flow becoming more zonal with time. Other than
some lingering cool air behind Tuesday mornings frontal passage,
the overall trend is for moderating temperatures for mid week
and into the last few days of March. Dry weather is anticipated
from Tuesday through Friday.
Next precipitation threat appears to be the weekend (March
30-Apr 1st). By that time temperatures are progged to be well
above normal so we may have to deal with some thunderstorms by
April Fools Day.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
As of 725 PM EDT Friday...
The vast majority of the region is now reporting VFR conditions,
but winds continue to remain very gusty. These gusty winds will
continue into the evening hours, especially at the highest
elevations. Speeds will start to decrease first later this
evening across the Piedmont region and also the mountain
valleys.
Precipitation will be limited to upslope rain/snow showers
across parts of southeast West Virginia, west and southwest of
KLWB. This will be the same region where any sub-VFR conditions
will be possible through roughly 06Z.
VFR conditions are still expected for the entire area on
Saturday with winds still gusty, but with speeds notably less
than those realized today.
Confidence is medium to high for all forecast elements through
06Z with high confidence between 06Z-24Z.
EXTENDED AVIATION DISCUSSION...
VFR conditions expected Saturday night into Sunday. Sub-VFR
conditions are possible Monday and possibly into Tuesday with
rain. Dry weather on tap for Wednesday.
&&
.FIRE WEATHER...
As of 330 PM EDT Friday...
Strong Gusty Winds through Tonight...
Continued Breezy Saturday...
Low Humidity Saturday Afternoon...
A strong cold front will move through the area this evening
promoting strong gusty winds. Wind gusts of 40 to 60 mph are
possible along the higher mountain ridges with 25 to 40 mph
winds in the valleys and across the piedmont. These winds
will gradually diminish during the day Saturday.
Concern Saturday will be the lingering wind and lowering
humidity. Humidity minimums Saturday afternoon are expected
to dip into the 15 to 25 percent range. This will favor
potential for rapid spread of brush fires, primarily for those
areas that did not receive meaningful rain or snow Thursday and
and Friday.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...Wind Advisory until 6 AM EDT Saturday for VAZ007-009>014-
018>020-022>024-032>035.
High Wind Warning until 6 AM EDT Saturday for VAZ015>017.
NC...Wind Advisory until 6 AM EDT Saturday for NCZ003-019.
High Wind Warning until 6 AM EDT Saturday for NCZ001-002-018.
WV...Wind Advisory until 6 AM EDT Saturday for WVZ042>044-507.
Winter Weather Advisory until 5 AM EDT Saturday for WVZ508.
&&
$$
SYNOPSIS...PM/WP
NEAR TERM...DS/KK
SHORT TERM...PM
LONG TERM...PM
AVIATION...DS/KK/WP
FIRE WEATHER...PM