Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/09/18
Area Forecast Discussion
National Weather Service Albany NY
951 PM EST Mon Jan 8 2018
.SYNOPSIS...
A cold front and an upper level disturbance will bring
some lake enhanced snow showers overnight especially north and west
of the Capital Region. Temperatures will finally return to normal
values by tomorrow and reach above normal levels by later in the
week. After a dry day on Tuesday, some light freezing rain is
expected on Wednesday, which will change to plain rain for Thursday
into Friday.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 949 PM EST...A cold front and an upper level trough
continue to race towards the region from the eastern Great Lakes
Region, and southeastern Ontario and southwest Quebec. Temps
continue to warm slightly in the warm sector ahead of the cold
front. Some rain showers are reported upstream across the cntrl
NY at KSYR and KRME, but this this should transition to snow
showers over the next few hours with the cold front pushing into
western NY, as snow showers are occurring near KROC. The latest
3-km NAM and HRRR continue to show enough lake moisture being
tapped in the southwest to west flow for some 1-3" snow amounts
for the western Adirondacks and western Mohawk Valley. The
cooling down of the low to mid-level and upslope enhancement
look to persist into the early to mid morning hours. We will
keep the advisory up at least a little longer for
Herkimer/Hamilton and northern Fulton Counties.
Please see our Public Information Statement with the latest
snowfall amounts from this event.
Temps should start to drop off between 3-6 am with lows falling
back into the upper teens to mid 20s, as the west winds increase
at 10-20 mph with the modest cold advection with the frontal
passage. The upper trough passage will move through later in the
morning into the afternoon.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/...
On Tuesday into Tuesday night, dry weather can be expected as
high pressure slides across the area. Highs on Tuesday will be
in the mid 20s to mid 30s. Lows on Tuesday night look chilly
thanks to good radiational cooling, with lows in the single
digits to mid teens.
On Wednesday, the next storm system will be approaching from the
Great Lakes thanks to the fast zonal flow in place aloft. Temps
aloft will be warming considerably, with 850 hpa temps surging
to +4 to +7 C thanks to the strong west to southwest flow
aloft. Some light precipitation will be spreading across the
area from west to east for late in the day Wednesday into
Wednesday night. Although precip looks light, with these warming
temps aloft, most areas will see a period of freezing
rain/drizzle before temps at the surface warm above freezing.
Temps should be rising all day Wednesday and even into Wed night
thanks to the expected southerly flow, but it will take a while
for all areas to rise above freezing. Parts of the Adirondacks
and southern VT may not rise above freezing until sometime on
Thursday thanks to the stubborn cold dense air that will be
trapped within the tight mountain valleys. All areas might see a
light glaze of ice, so will make mention in the HWO that a
period of hazardous travel will be possible due to icy
conditions. Even when sfc temps do rise above freezing, it may
take a little while for the ground to respond since it has been
so frigid cold for so long and freezing rain may still accrete
for a while after the sfc air temps are above freezing. Temps
should rise through the 20s on Wednesday into the low to mid 30s
by Wed night.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
A very challenging long term forecast period for the northeast
corridor as we start off with increasing milder temperatures through
the end of the work/school week. Thereafter, arctic boundary
attempts to sneak southward before lifting northward again as a warm
front through the first half of the weekend before more arctic air
attempts to return for the second half of the weekend.
A highly energetic and increasing amplified flow across NOAM and per
the global model consensus, seems our region will be downwind of the
amplification upstream leaving rising heights across the I95
corridor through the first half of the weekend. This should allow
for any wintry mixture we observe Wednesday night, which could be a
period of freezing rain/drizzle and sleet slowly transitioning to
rain through the daylight hours Thursday. In fact, H850
temperatures climb back toward +10C as a elongated southerly flow
becomes further entrenched across the region. Furthermore, PWAT
anomalies Friday climb to around +4 Standard Deviations above normal
so the potential for some moderate rainfall exists. This should
equal to temperatures climbing back into the 40s for most of the
region. The last time Albany reached 40F+ was back on December 20th
2017.
Friday night into Saturday becomes quite challenging as global
models hint at an arctic boundary attempting to slip southward
Friday night to the north and west of Albany. As moisture remains
in place, with additional moisture transport advecting northward, a
period of wintry mixture will be possible. Then next surface low
with approaching short wave on the base of the upper trough across
the lower Tennessee Valley becomes increasingly negatively tilted
late Saturday into Saturday night as warm advection should allow
this arctic boundary to lift northward through Saturday.
As this surface low tracks northeastward along the I95 corridor,
periods of rain should taper back to showers until the surface low
passage overnight Saturday. Ensembles offer a variety of ideas here
so a low confidence forecast as too just how fast the arctic air
returns late at night into Sunday remains to be seen with respect to
timing. Sunday should be much colder with any liquid falling
turning back to snow showers.
Temperatures will become above normal for a period of time before
returning back to normal or below normal with precipitation trending
above normal.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
A cold front continues to approach eastern New York and western
New England from the eastern Great Lakes Region tonight. This
front will move through in the morning. The upper level trough
will follow during the day, as high pressure will ridge late in
the afternoon into Tuesday night.
Conditions vary from low VFR to high MVFR in terms of cigs at
KGFL/KALB/KPOU/KPSF early this evening in the wake of a short-
wave passage. Skies will continue to be broken to overcast most
of the night with cigs in the 2.5-4 kft AGL range. Some snow
showers/flurries may impact KGFL/KPSF, as VCSH groups were
used. In the wake of the frontal passage between 09Z-13Z/TUE,
the winds will increase from the west to northwest, as cigs will
become sct-bkn with stratocumulus between 3.5-5 kft AGL. Some
MVR cigs may linger a bit at KPSF/KGFL, but raised the cigs to
VFR levels after 12Z. Expect VFR conditions into the afternoon
in the cold advection and subsidence in the wake of the front.
The winds will be south to southwest at 5-15 kts with some gusts
20-25 kts at KALB/KPSF. The winds will increase from the west to
northwest in the late morning at 10-16 kts with some gusts in
the 25-30 kt range at KALB/KPSF into the afternoon, before
diminishing between 22Z/TUE to 00Z/WED.
Outlook...
Tuesday Night: Moderate Operational Impact. Chance of RA...FZRA.
Wednesday: Low Operational Impact. Slight Chance of RA.
Wednesday Night: High Operational Impact. Likely RA.
Thursday: High Operational Impact. Likely RA.
Thursday Night: High Operational Impact. Likely RA.
Friday: High Operational Impact. Likely RA...SN.
Friday Night: Moderate Operational Impact. Chance of SN.
Saturday: No Operational Impact. NO SIG WX.
&&
.HYDROLOGY...
After recent very cold weather, river and lake ice has become
increased across the region. Based off temperature analysis,
river and lake ice is estimated between 7 and 15 inches thick.
Although temperatures are milder today, it will still be near
or slightly below normal and near normal temperatures are
expected for tomorrow into Wednesday.
Some light snow is currently falling across the area, but the
bulk of the snowfall (about 3 to 6 inches) should be
concentrated across the Adirondacks, western Mohawk Valley and
southern Vermont. Outside of those areas, amounts will generally
be under 2 inches. This snowfall won`t have any immediate
hydrologic impact. Some light freezing rain is also possible on
Wednesday into Wednesday night, although amounts will generally
be light.
By late in the week, temperatures will rise above normal and a
period of rainfall is expected as well for Thursday into Friday.
The combination of rainfall and snow melt will allow for river
and stream levels to increase. Depending on just how much
rainfall occurs and how warm temperatures get (and for how long)
will determine if any hydrologic impacts occur. There may be the
potential for ice jams and flooding if rainfall is excessive and
temperatures remain mild for an extended period of time, so
stay updated with the latest forecasts through the 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...None.
NY...Winter Weather Advisory until 7 AM EST Tuesday for NYZ032-033-
038-082.
MA...None.
VT...None.
&&
$$
SYNOPSIS...Frugis/JVM/Wasula
NEAR TERM...Wasula
SHORT TERM...Frugis/JVM
LONG TERM...BGM
AVIATION...Wasula
HYDROLOGY...Frugis/JVM
Area Forecast Discussion
National Weather Service Caribou ME
1028 PM EST Mon Jan 8 2018
.SYNOPSIS...
Low pressure tracking to the northwest will bring a cold front
across the area Tuesday morning. High pressure will build in
from the west Wednesday morning and then move east Wednesday
night. A warm front will slowly cross the region Thursday into
Thursday night.
&&
.NEAR TERM /THROUGH TUESDAY/...
1020 PM Update...
Radar showed snow pushing into the New Brunswick w/the obs
supporting this as some sites such as Millinocket and Houlton
had seem some partial clearing. IR satl imagery showed clouds
moving back in from the sw. Sfc analysis had the occlusion
lifting across northern areas. RAP soundings did show some llvl
moisture tucked in along the coast and temps were running in the
lower 30s. Added the mention of patchy freezing drizzle for the
coast through early morning hrs but it should not cause any
icing issues. Received a report of light freezing drizzle along
the Washington County coast. Temps pretty much holding in the
teens elsewhere for the most part and should hold that way
overnight.
The cold front is expected to arrive into western areas by
morning and slide eastward across the region by the afternoon.
Followed the daycrew`s assessment of bringing a round of snow
showers from w to e by morning. The latest run of the RAP and
HRRR were handling things quite well.
Previous Discussion...
Cold front mvs thru tomorrow with just scattered snow showers
expected in the mrng acrs the northwest as upr lvl trof works
its way thru the area. Temps wl warm to abv normal with lwr 30s
in the south and m/u 20s acrs the north bfr cold advection
returns. Expect gusty nw winds as mixing deepens drg the aftn.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
On Tuesday night, high pressure builds and the upper trough
will move eastward away from the state. Being on the east side
of the high, the expectation is that winds won`t drop off and
allow any steep radiational inversions, but the air mass will be
cold enough for widespread single digit readings. Did make a
some downward adjustments below guidance resulting in few
subzero readings. The high will crest over the area on Wednesday
with some morning sunshine, but high clouds will steadily
increase from late morning onward as the upper ridge crosses the
region. Highs will moderate into the 20s for most of the area
and even climb to the freezing mark on the coast. On Wednesday
night, light warm frontal precipitation will arrive and
temperatures will tend to rise from evening readings. It will be
mixed precipitation amounting to just a few hundredths on an
inch. The biggest concern will be light freezing rain and
drizzle as colder air remains entrenched at the surface. The
precip may start as freezing rain at Bangor and could generate
very slick roads. Since any measurable freezing precipitation
necessitates a winter weather advisory, it`s possible an
advisory will be needed. The steadier precipitation will end
later in the night, but a steep frontal inversion will remain in
place and some drizzle or freezing drizzle cannot be ruled out
on Thursday. Temperatures at H925 will reach around 10C, but
surface temperatures will remain in the 30s and lower 40s under
the inversion on Thursday. This is below guidance and leaned
this direction because the surface warm front will remain west
of the forecast area.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
A wet, icy, and potentially messy scenario is ahead for the end of
the week. A series of low pressure systems along a frontal boundary
to our northwest Thursday night will combine with a large high well
east of the east coast to bring warm air north across the entire
area. Some light rain and fog is likely Thursday night. Rain may
become heavy for a period on Friday ahead of a strong Arctic cold
front pushing toward the region. Arctic high pressure will build to
our north Friday night as a new low lifts up from the southeastern
states. Warm moist air will pull north in the mid and upper levels
as cold Arctic air filters in, in the low levels. This sets the
stage for a potentially significant sleet and ice storm situation
Friday night into Saturday. Right now central and Downeast areas are
favored for the heavier icing Friday night into early Saturday with
sleet and snow across the far north. Precipitation may change over
to rain across coastal Downeast areas on Saturday with some sleet
and freezing rain pushing into the north as the low center lifts
north. Precipitation should taper off to freezing drizzle and
drizzle Saturday night as the low lifts north over the area and a
dry intrusion pushes north. Cold and dry weather will follow Sunday
through early next week.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: IFR conditions expected in light snow through 05z at
FVE, and near 01z at remaining terminals. Restrictions gradually
improve to MVFR during the day.
SHORT TERM: Predominately VFR conditions are expected Tuesday
night into Wednesday evening. On Wednesday night, cigs will
steadily decrease to IFR for all sites and continue through
Thursday. Freezing rain and drizzle is a threat for all
terminals Wednesday night into Thursday morning.
&&
.MARINE...
NEAR TERM: Gale warning in effect for outer waters tonight with
SCA for intra-coastal. Expect that core of winds will diminish
by midnight and remain at SCA levels into Tue afternoon with
brief chance for gales in cold advection. Seas will remain 6-10
feet on outer waters and 3-6 feet in the intra-coastal.
SHORT TERM: SCA conditions will persist into Tuesday night with
light freezing spray. Another SCA...without any freezing
spray...will likely commence Wednesday night and persist into
Thursday. These SCA conditions will most likely be just over the
outer waters.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...Small Craft Advisory until 1 PM EST Tuesday for ANZ050>052.
&&
$$
Near Term...Hewitt
Area Forecast Discussion
National Weather Service Charleston SC
1004 PM EST Mon Jan 8 2018
.SYNOPSIS...
Arctic high pressure will move off the U.S. East Coast allowing
for a moderation in temperatures this week. A trough will
persist in the nearby Atlantic early this week with weak low
pressure remaining south of the area. A cold front will move
through Friday night followed by a secondary front Saturday
night.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 10 PM: KCLX indicated a patch of light to moderate
reflectivity just north of Jenkins County. Overall, it appears
that the light rain has been gradually decreasing through the
mid evening hours. However, sfc observations indicate that areas
under the returns were observing light rain with temperatures in
the mid 40s. I will update the forecast to indicate CHC to SCHC
PoPs across the far inland counties. Otherwise, temperatures
will be adjusted to align with recent hourly observations.
As of 630 PM: Light returns have been detected by KCLX over the
SE GA coast early this evening. HRRR indicates that coverage
and intensity of the returns will increase through the rest of
the evening. I will update the forecast to add a mention of
sprinkles to the forecast across SE GA early this evening, then
a SCHC of light rain. Temperatures will remain well above
freezing through tonight.
Previous Forecast:
Tonight: Aloft, the forecast area will sit on the northeast
periphery of a closed low diving into the Gulf of Mexico. At the
surface, high pressure will persist north of the area as a
surface low associated with the low aloft will remain southwest
of the area. The main forecast issues will be the potential for
light precipitation inland, and the potential for fog/stratus.
Regarding rain chances, the area will continue to be on the
periphery of larger scale forcing for ascent. As the main slot
of forcing shifts to along the Gulf Coast, the ongoing
precipitation to our west will shrink in coverage. We could see
a few showers brush our far inland zones, but the chances are
low and the impacts minor. Instead, it seems more likely we
could see some inland drizzle where fog is able to develop
tonight. The airmass across the region has warmed and moistened
significantly from previous days. However, the ground continues
to be uncharacteristically cold, especially in areas where the
most snow occurred last week and remained on the ground the
longest. As this warmer and more moist airmass settles across
the cold ground surface tonight, at least patchy fog is
expected. The threat is greater across an area that stretches
across Beaufort, Colleton, Dorchester, Berkeley, and Charleston
counties. Many locations across this area are seeing their most
significant snow melt yet, so this appears the prime area for
fog development. Have added areas of fog to this region, and
will also add a mention of locally dense fog to the Hazardous
Weather Outlook. Low temperatures across the forecast area are
expected to remain above freezing for the first time this year,
with lows ranging from the upper 30s for inland portions of
southeast South Carolina, to the upper 40s along coastal
Georgia.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
High pressure will build in from the north Tuesday behind a
departing shortwave trough helping to keep deep low pressure
over the eastern Gulf of Mexico. A coastal trough will linger
just offshore through the period. There could be some showers
from time to time through Wednesday night, mainly across GA and
near the lower SC coast where the deeper moisture is
anticipated. By Thursday the trough should push inland with
deeper moisture advecting in from the south leading to higher
rain chances, especially across SC where the best low-level
moisture convergence should be. Sea fog could also develop and
linger near coastal areas even during the daytime, especially
later in the period.
Temperatures will be above normal through the period,
especially by Thursday when 70s will be possible. However the
degree of warming will likely depend on how significant the
morning low clouds/fog will be, including any sea fog near the
coast.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Models are in pretty good agreement with the synoptic pattern
through the period. A potent shortwave embedded within an
amplified upper trough will help push a cold front through the
area late Friday. A band of precipitation will accompany the
front which will quickly push offshore by Saturday morning. A
couple rumbles of thunder aren`t out of the question, but
instability is quite limited. Cool and dry high pressure will
build in wake of the front and persist into early next week.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
Extensive high clouds will remain over the region tonight,
thinning around daybreak Tuesday. The primary forecast challenge
will be the development of restrictive stratus and fog late
tonight into Tuesday morning. However, the high cloud cover will
yield low confidence on the timing and category of
restrictions. Based on MOS and NAM forecast soundings, I will
expect the greater potential for stratus and fog will occur over
the region of lingering snow cover around KCHS. In fact,
forecast soundings show a very strong boundary layer inversion,
trapping llvl moisture below 1 kft. The potential for
restrictions will be highlighted with a TEMPO from 11-15Z for
IFR visibility and MVFR ceilings. At KSAV, MOS and forecast
soundings favor restrictions during the late night hours, with
the TAF featuring MVFR cigs/vis. Similar to KCHS, the early
daylight hours could see IFR ceilings, highlighted with a TEMPO.
Conditions should return to VFR by mid day.
Extended Aviation Outlook: Flight restrictions likely at times
through the week, mainly each night due to low clouds/fog, then
due to showers Thu and showers and possible thunderstorms Friday
into Friday night. Breezy conditions likely Friday/Saturday.
&&
.MARINE...
Tonight: A weak coastal trough will remain in the vicinity
early, but then weaken and become somewhat indiscernible through
the night. Winds will bounce around between northeasterly and
easterly with speeds topping out in the 10-15 knot range. Seas
will be in the 2-4 ft range.
Tuesday through Saturday: A coastal trough will linger over or
near the area through mid week before dissipating as a cold
front approaches from the west and then pushes through Friday
night. Winds will remain elevated but will mainly stay below
Advisory levels /25 kt/. However, building seas will lead to
Advisories starting in the offshore waters Tuesday night and
then eventually into at least the SC waters. Otherwise, sea fog
will become likely over the cool nearshore waters mid to late
week as low-level moisture increases across the area ahead of
the cold front. Dense Fog Advisories will be possible for
visibilities of one half nautical mile or less.
&&
.EQUIPMENT...
The temperature/dewpoint sensor on the KCHS ASOS is still
malfunctioning but the observer is manually augmenting the
observation until the problem can be resolved. Parts are on
order.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.
&&
$$
NEAR TERM...NED
SHORT TERM...RJB
LONG TERM...ECT
AVIATION...NED/RJB
MARINE...BSH/RJB
EQUIPMENT...
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
538 PM CST Mon Jan 8 2018
.UPDATE...
00Z Aviation forecast below.
&&
.AVIATION...
VFR conditions with periods of high cirrus tonight and Tuesday.
NW-NE winds diminishing to around 5 kts or less this evening. A SE
wind around 5 kts will develop after 15Z Tue at SAT and AUS and
around 10 kts at DRT.
&&
.PREV DISCUSSION... /ISSUED 328 PM CST Mon Jan 8 2018/
SHORT TERM (Tonight through Tuesday)...
No major weather highlights in the short term as near to slightly
above normal temperatures occur today and Tuesday under clear skies.
Latest water vapor and RAP analysis indicate south-central Texas is
on the back side of a departing shortwave trough now over the Gulf of
Mexico with upstream shortwave ridging occurring over the desert
Southwest. The deeper north flow today will relax overnight with
surface winds shifting to the east and then the south by tomorrow as
the in situ airmass modifies. Despite the gusty winds today,
temperatures have reached into the mid 60s to low 70s across the
region. Given the lighter flow and further airmass modification with
warmer H925 temperatures tomorrow, surface temperatures should be
similar to 1-2F degrees warmer. PWATs will remain below 0.5" through
Tuesday with clear skies persisting.
LONG TERM (Wednesday through Monday)...
Main highlight during this period will be a strong cold front passage
Thursday morning that will bring only limited rain chances to far
east Coastal Plains locations. Gusty north winds will occur behind
the front Thursday and a series of freezing low temperatures are
expected late week and into the weekend.
One last warm day will occur Wednesday as above normal temperatures
of +5F to +8F degrees occur as H5 flow becomes southwesterly.
Moisture will attempt to return to the region with surface dewpoints
increasing into the mid 50s and PWATs to 0.9-1.1" (75th percentile
for this time of year) across the Coastal Plains Wednesday to early
Thursday morning. There is still some question to overall moisture
depth and flux and any destabilization appears minimal at this time.
Despite the stronger mid-level forcing and surface convergence,
models suggest mid- and upper-levels will remain too dry for
widespread rain showers and a confined warm sector. The far eastern
Coastal Plains will likely have the only limited rain chance with the
passage of the front. Gusty north winds will occur behind the front
with temperatures falling back to near to slightly below normal
Thursday.
The driest air will arrive Friday and linger through the weekend with
dewpoints in the teens and 20s. A series of freezing low
temperature mornings will be likely as a strong surface high
pressure system develops over the Central Plains.
By early next week, long range models indicate a warm front shifting
north over the region that could bring increased rain chances in
conjunction with a brisk moving southern jet-stream branch Pacific
trough. Stay tuned as this system evolves and confidence narrows on a
particular solution.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 40 70 45 71 53 / 0 0 0 - 10
Austin Bergstrom Intl Airport 39 69 43 71 52 / 0 0 0 - 10
New Braunfels Muni Airport 39 70 42 71 50 / 0 0 0 - 10
Burnet Muni Airport 37 69 43 70 48 / 0 0 0 - 10
Del Rio Intl Airport 44 71 44 71 49 / 0 0 0 0 -
Georgetown Muni Airport 39 68 43 70 51 / 0 0 0 - 10
Hondo Muni Airport 40 72 42 73 48 / 0 0 0 - 10
San Marcos Muni Airport 39 70 42 71 51 / 0 0 0 - 10
La Grange - Fayette Regional 40 66 44 71 54 / 0 0 0 - 10
San Antonio Intl Airport 41 70 44 71 52 / 0 0 0 - 10
Stinson Muni Airport 41 70 44 72 52 / 0 0 0 - 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Mesoscale/Aviation...Runyen
Synoptic/Grids...05
Public Service/Data Collection...YB
Area Forecast Discussion
National Weather Service Grand Forks ND
708 PM CST Mon Jan 8 2018
.UPDATE...
Issued at 657 PM CST Mon Jan 8 2018
Mid level clouds expected to thicken over the area through the
late evening... with a eastern ND and far southeast ND near the
midnight hour. Otherwise... no significant changes to the forecast
are expected. An update Aviation discussion is attached below.
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 329 PM CST Mon Jan 8 2018
An upper level wave is moving east across eastern MT and into
western ND currently, while high pressure resides at the surface
across the Red River Valley and northern MN. The upper wave will
drift east southeast tonight...and likley clip far southeast ND.
This wave may produce some light freezing rain or snow...but only
a very little amount. The GFS and some of the hi-res models have
been promoting this event, but still the confidence is rather low
due to a dry layer in the low levels. The forecast will be focused
on this feature in the near term and then transition to fog
overnight. Warm moist air pushes back northward tonight and
tomorrow ahead of a developing low pressure system. Fog will be
possible in the west from Langdon to Gwinner as depicted by the
HRRR and RAP.
On Tuesday, the warm air aloft will result in mild lows in the
morning and highs in the low to mid 30s across much of the region.
Clouds could be a hindrance as well tomorrow...but the wind will
be generally light--from the south at 10 mph.
.LONG TERM...(Tuesday night through Monday)
Issued at 329 PM CST Mon Jan 8 2018
A surface low will be moving across far southern Canada Tuesday
night into Wednesday dragging an arctic cold front eastward through
the area. Ahead of this front, forecast soundings show a dry mid
level above a saturated column mainly below H9. There is also
suggested to be some weak mid-level lift ahead of an incoming trough
early Wednesday as well. Minimum wet bulb temperatures in the low
levels layer are around -5 to -8 degrees Celsius hinting to a lack
of ice formation increasing the chance of freezing drizzle rather
than snow. Have adjusted the forecast to show this early Wednesday
in northwestern Minnesota. Closer to the cold front, strong cold air
advection near the surface should precipitate available moisture
while ice nuclei aloft still lacking due to dry mid-levels. This
introduces the chance of seeing some freezing rain attached and just
behind the cold front before quickly changing to snow. With the
majority of our snow coming the form of frontogenetical lift in the
H8-H7 layer Wednesday afternoon into early Thursday behind the
progressive cold front, snow should not linger around the region, at
least the steadier, accumulating snow. This should aid in keeping
snow totals on the tamer side unlike our neighbors to the south and
east where a Colorado low travels along the aforementioned cold
front well to our south and east. Questions still remain on exactly
where heaviest snow falls which will influence where blowable snow
will reside. Confidence in gusty northerly winds is high, especially
within the southern Red River Valley, however the lack of confidence
in significant snowfall placement and how the recent warm up will
impact the "blow-ability" of current snowpack keeps blowing snow
potential in question. Gusty northerly winds of 25-30 mph behind the
front will remain elevated through Wednesday night contributing to
frigid wind chill values into the thirty degrees below zero range.
Precipitation chances end west to east around early Thursday leaving
the latter half of Thursday dry and cold. Dry conditions may be short
lived as a clipper system is expected to move into the region around
Friday. Track of this clipper is still uncertain, however the chance
of a quick shot of snow and wind remains in the forecast Friday. A
couple of arctic high pressures are expected to set up over the
region this weekend into early next week keeping conditions dry and
cold. Will likely be talking about wind chill criteria again from
late this week into early next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 657 PM CST Mon Jan 8 2018
Across the area expect VFR conditions with patchy mid level
clouds and light winds through 06z. Aft 06z...VFR conditions will
persist across the Red River Valley corridor and across northwest
MN. Patchy fog or low stratus is possible between 06z and 12z in
the Devils Lake Basin...through skies will stay mainly VFR. Patchy
MVFR cigs will move across far southeast ND from 06z through
11z... with widely scattered flurries or light freezing rain
possible. After 12z... expect areas of MVFR CIGS over the Devils
Lake Basin... with VFR conditions elsewhere.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
UPDATE...Gust
SHORT TERM...Knutsvig
LONG TERM...CJ
AVIATION...Gust
Area Forecast Discussion
National Weather Service Houston/Galveston TX
827 PM CST Mon Jan 8 2018
.UPDATE...
A low stratus deck is currently situated just west of the TX/LA
state border and expected to move westward into our area
overnight tonight. Ahead of these low clouds, patchy fog
development is possible as early as midnight for the northeast
counties, and then spreading further south through 9 AM CST. While
fog development is not as likely under the low stratus deck,
cannot rule out low clouds making it to the surface. Otherwise,
forecast looks on track for the overnight period.
22
&&
.PREV DISCUSSION... /ISSUED 718 PM CST Mon Jan 8 2018/
AVIATION...
Clear skies and relaxing winds this evening. Guidance is very
bullish in stratus deck expanding back to the west after midnight
and moving into the UTS/CXO/IAH/HOU terminals between 06-09z then
persisting through 15-16z. Guidance was verifying out to be a
little to far west with the back edge of the clouds but as the
low level profile cools rapidly anticipate that the trapped
moisture/cooling will indeed lead to the redevelopment of the
stratus deck. Some areas to the west of the deck should even see
some IFR fog and wouldn`t rule out some LIFR in the window between
10-13z. Skies should scatter out quickly with heating around
15-16z. Northerly winds relaxing tonight becoming east and
northeast after sunrise then clocking around to the east and
southeast through the late afternoon hours. Stratus deck
redeveloping late evening 05-08z/Wed probably downwind of
Galveston Bay.
45
PREV DISCUSSION... /ISSUED 314 PM CST Mon Jan 8 2018/
DISCUSSION...
Post-frontal Monday with moderate northwesterly winds pulling down
drier air along the backside of north-central Gulf troughing. Full
sun has countered the cold air advection as evidenced by the 2 PM
regional temperature middle 60 temperature readings. This evening`s
forecast shouldn`t be all that tricky but recent model runs are
messaging the formation of lower cloud decks and this has introduced
doubt with the near term forecast. More of this doubt is centered
on the NWP data rather than on the official forecast as...other
than some magical serious-retrograde of the Sabine River Valley
wraparound moisture...there is no meteorological reasoning to a
Tuesday morning low stratus deck. Even if this progressively eastern-
moving northern Gulf trough axis suddenly ground to a halt and
retro`ed westward...any moisture would be upper-mid layer moisture
and not lower layer per (post-frontal CAA) lower 600 mb layer air
being so bone dry. There may be low enough eastern CWA TDDs to
instigate saturation but this `signal` would lend itself to more
of a fog argument and not stratus. SREF early Tuesday fog
probabilities are nearly non-existent as well but...with dew point
depressions expected to fall within 3 degrees of colder
(anticipated clear sky) ambients and a lingering damp ground from
last night`s rain...have decided to place northeastern CWA patchy
fog into the early Tuesday morning forecast. There will be a much
higher chance for late Tuesday into Wednesday morning shallow
interior fog development...possibly dense...as tomorrow`s return
flow warms dew points up to near relatively-warmer Wednesday
morning middle 40 minTs.
The mid-week discussion turns from inland fog to the next cold
frontal passage timed to come across the area Thursday during the
day. While not expected to be a huge rain maker...there may be an
hour or two in the morning where a few isolated cells go up as
thunderstorms. The main story from this fropa will be the much colder
and drier backing air mass that will descend over eastern Texas
in delayed fashion through Saturday. Progs are all leaning towards
mid-level cooling into the low single digits that would translate
to weekend mornings falling into the inland 30s (light freeze up
north) and days struggling to meet or maintain the 50s. As of now...
Sunday is forecast to be the coldest day as a reinforcing shot/front
of colder air dives down Saturday. Late period easterly wind leans
itself towards an isentropic upglide...warm air advection scenario.
Column should warm up enough to preclude the mention of any (northern
CWA) frozen precipitation. Anticipating cool and overcast with light
rain/drizzly-type weather pattern this time next week. 31
MARINE...
Strong northwest winds will slowly diminish this evening but a
moderate offshore flow will persist over the offshore waters.
Seas remain elevated and will extend the SCA through 04z primarily
for the elevated seas. Surface high pressure over the southern
plains will move east and winds will veer to the east and
eventually the southeast on Wednesday. The gradient will begin to
tighten on Wednesday as low pressure over the central plains
deepens. The low will move east on Thursday and sfc winds will
become SW and slacken a bit in advance of an approaching cold
front. The front will cross SE TX on Thursday afternoon and winds
will become NW and increase. A Wind Advisory looks likely along
the coast and an SCA for the bays and nearshore waters. A Gale
Watch/Warning will be required for the offshore waters and
sustained winds will approach 30 knots with frequent gusts
exceeding 40 knots. Onshore winds will return on Sunday and
strengthen next Sunday night into Monday.
The strong offshore fetch will feature a favorable trajectory to
drive water out of the bays and a Low Water Advisory will likely
be needed Thursday night into Friday. Current projections show
water levels 2.25 feet below MLLW. Navigation over parts of the
ship channel and upper reaches of Galveston Bay will be difficult.
43
AVIATION...
Surface high pressure is bringing VFR conditions to all of SE TX
this afternoon and clear skies are expected for much of the
evening. Will be making a significant change to the 18z TAFs at
the 21z update. The NAM and the HRRR continue to support wrap
around clouds backing into the area from the east tonight,
beginning around 04z and slowly spreading west. The HRRR is
indicating IFR ceilings but the NAM soundings support MVFR. Will
be introducing MVFR ceilings to eastern TAF sites between 03-06z
and carry the lower ceilings through 18z Tuesday. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 40 62 46 68 56 / 0 0 10 10 20
Houston (IAH) 44 62 47 69 57 / 0 0 10 10 20
Galveston (GLS) 48 58 51 64 59 / 0 0 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION until 1 AM CST Tuesday for
the following zones: Waters from Freeport to the Matagorda
Ship Channel from 20 to 60 NM...Waters from High Island to
Freeport from 20 to 60 NM.
&&
$$
Discussion...22
Area Forecast Discussion
National Weather Service Wilmington NC
1039 PM EST Mon Jan 8 2018
.SYNOPSIS...
High pressure will move farther offshore tonight. Passage of a
weak cold front overnight, will allow a wedge of high pressure
to set up across the Carolinas through mid week. A warm front
will bring a chance of rain by late Thursday, with noticeable
warming Friday. A few showers will accompany a cold front
crossing the coast on Saturday, opening the door for colder air
Sunday and early next week, though not as cold as recent air.
&&
.NEAR TERM /THROUGH TUESDAY/...
As of 1000 PM Monday...Coastal trough is dissipating offshore while
a weak cold front/trough drops in from the NW. This second boundary
will push through the CWA by morning followed by wedging of a
surface high pressure through Tuesday. The upper level pattern is
clearly evident on GOES-East WV imagery with a deep closed low over
the GOM with some diffluence and a vort streamer angled NE from this
feature into the eastern Carolinas. Concern for the rest of the
overnight involves any light rain chances, as well as fog/stratus.
Dewpoint depressions along the coast are collapsing towards 0 thanks
to better moist advection from the Atlantic this aftn. At the same
time, cloud cover is increasing from the SW which is helping to
offset the cooling and fog potential. SREF probs remain very high
for fog overnight, while the HRRR and local UPS fog tool have fallen
back a bit and suggest just some light fog along primarily the Grand
Strand. This seems most plausible and have shown in the Wx grids as
such. Locations further inland appear to be too dry, and won`t fall
to crossover values tonight, as we finally stay above freezing for
the first time this year! Additionally, moisture associated with
weak forcing aloft is shown in forecast profiles to be too light for
any measurable precip reaching the surface despite echoes showing up
on KLTX radar across the Pee Dee. This will manifest only as virga,
and have kept POP silent overnight. Do expect some stratus to
develop behind the weak front towards daybreak as shown by most
guidance and visible behind the boundary on latest GOES-East fog
products, but much of this may be confined to the mid-levels as
guidance has been too aggressive recently developing low-cloud decks.
Mins tonight will drop only into the mid 30s far NW, upper 30s near
the coast, more typical for this time of year, and a welcome relief
from the polar air mass that has engulfed our area so far in 2018.
After a relatively mild morning, temps will warm tomorrow with highs
reaching into the mid 50s most places despite what could be ample
mid-level cloud cover and NE winds.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 332 PM Monday...Zonal mid level flow locally atop a
cutoff upper low traversing Florida. This system and its
associated moisture and lift should remain far enough south to
preclude any effects on weather here other than some cloudiness.
Most of the Carolinas will have partly to mostly cloud skies
and unseasonably mild conditions Wednesday night. Wednesday
afternoon will also be mild but the daytime deviations from
climatology won`t be as impressive (the nighttime lows bolstered
by cloud cover). This system gets kicked eastward by a strong
low heading towards the Texas panhandle for most of the period.
Boundary layer flow will veer from NE at the surface to ESE
leading to some rather weak warm advection. Even so, Wednesday
night lows in the mid to upper 40s not only 10+ degrees above
climatology but also much warmer than most daytime highs from
this last cold snap.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 332 PM Monday...The extended forecast will feature a warm
front/cold front pairing, followed by cooling Sunday and early
next week. Both warm and cold fronts will be able to provide a
chance of liquid precipitation. Total QPF at this time, is best
fit to 0.25-0.50 inches Thu-early Sat. Friday in wake of warm
front passage, we may in fact see 70s, this not seen since mid-
December or so. Weekend maximums will be hammered back down
however by cold frontal passage Saturday, and an ensuing surge
of colder air Sunday and early next week, but it will not be as
frigid as the air mass recently. Stratiform precipitation with
the warm front late Thursday, will perhaps see a brief lull on
Friday, transitioning to showers late Friday and early Saturday
ahead of and along the cold front. Suffice to say large temp
swings in the extended, with maximums cooling to below 50, if
not by Sunday, Monday is poised to be a slightly cooler day.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
As of 00Z...Quite a bit of snow cover and/or wet soils persist
at the terminals, with moist air and cold air moving over this
cold surface. Confidence is moderate sub-VFR fog and stratus
development will occur generally after 06Z. However, confidence
is low as to the timing of onset, the extent of cig/vsby
deterioration, and time of improvement. This is mainly due to
scattered to broken mid- level cloud cover. Model soundings/MOS
guidance shows potential for IFR/VLIFR overnight through the
mid-late morning hours. The NAM guidance indicates the most
cloud cover and best flight categories. Have indicated after 06Z
IFR vsbys/LIFR cigs developing, improving around 15Z.
Extended Outlook...Late night/morning MVFR/IFR Wed due to fog.
MVFR Wed. Tempo MVFR/SHRA Thurs/Fri. Chance thunderstorms Friday
night. MVFR becoming VFR Sat.
&&
.MARINE...
NEAR TERM /THROUGH TUESDAY/...
As of 1000 PM Monday...Coastal trough wavering and weakening across
the waters will dissipate by morning as a weak cold front/trough
dips in from the NW. This will cross the waters into early Tuesday
producing a wind shift to the NE with a subtle increase in speed to
around 10 kts, rising further late in the day as the gradient begins
to pinch within a strengthening high pressure wedge inland. Seas
will be generally 2 ft much of the period, rising late to 2-3 ft as
the winds begin to increase on the pinching gradient.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 332 PM Monday...Onshore flow expected through the period.
Wind direction will show a slight veer from NE to E as weak
pressure falls occur in the Bahamas. Wind waves likely not to
change appreciably but increasing swell energy will be raising
predominant wave height, possibly calling for Small Craft
Advisory by the period`s end.
LONG TERM /THURSDAY THROUGH SATURDAY/...
As of 330 PM Sunday...Winds this period appear manageable, with
SE flow Thursday ahead of a warm front passage northward. Winds
will become S-SSW in wake of the warm front late Thu into Fri.
We may need an advisory this period not so much for the winds,
but elevated seas, due to a large fetch area offshore pointed
this way. As a result, 4-7 foot seas in a combination of SE
swell and moderate wind-seas is expected Thu into Fri. Friday
will be the breeziest day with southerly gusts, but strongest
wind-speeds well offshore where the milder waters reside.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.
&&
$$
NEAR TERM...JDW
SHORT TERM...MBB
LONG TERM...MJC
AVIATION...MRR/JDW
Area Forecast Discussion
National Weather Service Wilmington OH
929 PM EST Mon Jan 8 2018
.SYNOPSIS...
Weak high pressure will build into the region tonight, but will
move quickly east on Tuesday. Southerly flow will pull moisture
and much warmer air north into the area beginning Tuesday
night, which will result in a chance of rain showers through
Thursday. A more organized system will affect the region for
Friday into Saturday.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Satellite imagery show little change in extend of cloud cover
across the region this evening. It seems likely that these
clouds will remain through the night. RAP 950 mb relative
humidity still shows some decrease in the west before morning,
so cannot rule out some breaks in the clouds. Last of the lower
visibilities is pushing out of the far southern part of the
forecast area this evening. Still some question whether
additional fog will form across the area. It appears that for
this to occur, the ceilings would have to become very low. Still
seeing quite a bit of guidance suggesting visibility
reductions, but at this point not much confidence. So have just
kept some patchy fog in later tonight. With a little more
confidence in clouds remaining, have bumped up temperatures a
bit more.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
The center of the surface high will shift east into the
Appalachians on Tuesday. High level clouds will affect the
region throughout the day. Southerly flow will bring a range of
high temperatures for Tuesday, as the range from the mid 30s in
West Central Ohio to the lower 40s in nrn Kentucky.
Moisture will be pulled up into the region Tuesday night. As
isentropic lifts increases, scattered showers will develop after
midnight. After an early low in the evening hours, temperatures
will be on the rise, so removed the threat of any freezing pcpn.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
An active weather pattern will be in place across the region through
most of the long term period. With southerly flow and an increase
in moisture there will be the potential for fog Wednesday into
Wednesday night. In addition, drizzle and light rain will also be
possible at times Wednesday into Wednesday night.
Winds will pick up on Thursday and therefore expect fog to dissipate
during the day on Thursday. This increase in winds will also bring
warmer air into the region with highs in the 50s and 60s.
Precipitation chances will increase Thursday night into Friday as a
frontal boundary approaches and moves into the region. A
disturbance will then ride along this boundary Friday into Saturday.
The ECMWF has come more in line with the cooler solutions. With
this in mind there will be a greater potential for a wintry mix and
accumulating snowfall across the region with this system. The
changeover from rain to wintry precipitation is expected to occur at
this time Friday into Friday night. Winds will also pick up during
this time. Snow will continue into the weekend and temperatures
will be cool. Additional lake enhanced snow showers will be possible
on Sunday. Sunday night is expected to be the coldest night as
clouds begin to decrease and with snow cover expected to be on the
ground.
Most of the day on Monday is expected to be dry, however a weak
system on Monday will bring a slight chance of snow to northern
portions of the forecast area.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
MVFR to IFR ceilings across the region are expected to lower to
IFR area wide overnight. Could still see some visibility
restrictions, but at this time do not expect them to be lower
than the ceiling flight category. There is a fair amount of
uncertainty when the lower clouds will break with at least some
potential for that to occur before 12Z. But it seems much more
likely that clearing will be more in the 15Z-18Z time frame.
Thereafter, VFR will prevail with high clouds. Southwest winds
will continue to diminish tonight, become variable and
eventually become light southeast later in the period.
OUTLOOK...MVFR to IFR ceilings and visibilities likely Tuesday
night into Wednesday night and then again Thursday night into
Friday night. MVFR ceilings possible at other times.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...JGL/Sites
NEAR TERM...
SHORT TERM...Sites
LONG TERM...
AVIATION...
Area Forecast Discussion
National Weather Service Jacksonville FL
1027 PM EST Mon Jan 8 2018
...DENSE FOG ADVISORY THROUGH 9 AM TUESDAY...
.UPDATE...
Late evening surface analysis depicts high pressure (1025
millibars) situated along the Carolina coast. Weak low pressure
(1012 millibars) was centered along the Louisiana coast, with a
weak warm front moving northward along the Interstate 10 corridor.
Aloft...a stacked cyclone was moving slowly south- southeastward
off the Louisiana coast into the north central Gulf of Mexico.
This weather pattern was producing warm air advection over our
area per the veering low level wind profile displayed on the
evening sounding at Jacksonville. This warm air advection has
brought dewpoints up into the 50s region- wide, which is equal to
or above the near shore Atlantic water temperatures following the
extended cold spell over our region. This is a perfect set-up for
widespread dense fog formation, and sea fog quickly developed
along the coast during the mid to late afternoon hours following
the passage of northward moving showers. The GOES-E MVFR/IFR/LIFR
probability products show low stratus ceilings and fog advection
moving westward past the U.S. Highway 301 corridor, with 300 foot
ceilings recently moving over the Gainesville Regional Airport.
Temperatures range from the lower 50s at the beaches due to chilly
onshore winds, with mid/upper 50s for most inland locations as of
03Z.
Short-term high resolution models such as the HRRR have nailed the
inland expansion of fog and low stratus during the past several
hours, and we anticipate that dense fog advisories will eventually
be expanded to cover all but perhaps our northernmost counties in
southeast Georgia. Low level southeasterly winds will begin to
deepen on Tuesday, advecting higher moisture levels from the
Florida peninsula northward during the afternoon hours. Low
stratus and fog may be slow to erode during the early morning
hours, but a tightening local pressure gradient should dissipate
the murky conditions by late morning as shower coverage begins to
increase from the south. Higher rain chances are currently
expected for locations to the east of I-75 in Florida and
along/east of U.S. Highway 301 in southeast Georgia, mainly
during the afternoon hours tomorrow. Despite plenty of cloud
cover, highs will climb into the 70s over north central Florida
before rainfall coverage increases, with mid/upper 60s for
locations along and north of I-10. Breezy onshore winds will
develop during the afternoon hours on Tuesday along and east of
I-95 as our local pressure gradient tightens.
&&
.AVIATION...
LIFR conditions will prevail at SSI, the Duval County terminals
and SGJ through at least 13Z. IFR ceilings should reach GNV by
04Z, with LIFR then prevailing through at least 14Z. Northeasterly
surface winds will increase to around 10 knots at SSI and SGJ
around 14Z and then will strengthen to near 15 knots by 16Z, with
east-northeasterly surface winds increasing to around 10 knots
elsewhere. Scattered showers may begin to impact the regional
terminals after 18Z.
&&
.MARINE...
Sea fog will remain possible through at least the mid-morning
hours on Tuesday, and a Marine Dense Fog Advisory has been issued
for the near shore waters through 9 AM. Otherwise, high pressure
will remain situated to the north of our region through midweek.
Meanwhile, weak low pressure over coastal Louisiana this evening
will slide south-southeastward while weakening through midweek.
Our local pressure gradient will remain rather tight through
midweek, with onshore winds strengthening to near 15 knots in the
offshore waters later tonight and to Caution levels on Tuesday.
Onshore winds will strengthen to around 15 knots on Tuesday and
Tuesday night. Seas will continue to build, with Small Craft
Advisory (SCA) conditions likely developing over the Florida
offshore waters by late Tuesday afternoon or Tuesday evening. Seas
will likely remain at caution levels of 4-6 feet for the near
shore waters from Tuesday night through Thursday. A coastal trough
is expected to develop over our waters towards midweek, and weak
low pressure may develop along this trough and move northward
along the Florida Atlantic coast through Wednesday night. SCA
level seas will prevail through Thursday. A strong cold front will
then enter the southeastern states on Friday, crossing our
coastal waters on Friday evening. Offshore winds will strengthen
during this frontal passage, with SCA conditions possible offshore
by Friday evening.
Rip Currents: Elevated risk to continue this week due breezy
onshore winds and easterly ocean swells.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 64 50 66 56 / 10 20 30 40
SSI 56 51 62 56 / 30 30 50 60
JAX 61 54 68 58 / 10 20 40 60
SGJ 62 56 68 61 / 10 20 40 50
GNV 68 55 72 58 / 10 20 30 30
OCF 69 56 74 58 / 10 20 40 20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...Dense Fog Advisory until 9 AM EST Tuesday for Baker-Bradford-
Clay-Coastal Duval-Coastal Nassau-Flagler-Inland Duval-
Inland Nassau-Putnam-St. Johns-Union.
GA...Dense Fog Advisory until 9 AM EST Tuesday for Coastal Camden-
Coastal Glynn-Inland Camden-Inland Glynn.
AM...Dense Fog Advisory until 9 AM EST Tuesday for Coastal waters
from Altamaha Sound to Fernandina Beach FL out 20 NM-
Coastal waters from Fernandina Beach to St. Augustine FL
out 20 NM-Coastal waters from St. Augustine to Flagler
Beach FL out 20 NM.
&&
$$
Nelson/Enyedi/Corless
East Central Florida Forecast Discussion
National Weather Service Melbourne FL
913 PM EST Mon Jan 8 2018
.DISCUSSION...
Current...Winds through a deep layer continue to veer largely in
response to upr low apchg from the gulf. A more organized batch of
marine showers are apchg the southern coast attm with potential to
exhibit a lightning strike or two into the overnight hours. Ltst
HRRR guid indicates sct marine based showers and possibly an
isolated storm apchg the coast for the remainder of the night over
the Treasure cst and spreading nwd into early Tue morning as
upr low and attendant unstable conditions develop during the day.
With the fcst update wl add a fog mention for the areas around
Volusia co currently exhibiting fog coverage, with a chance of
thunder over the southern marine segments. Other parameters are in
good shape.
.prev disc...
Tonight-Tuesday...Cutoff mid-upper level low center will drop from
SELA to offshore the SWFL coast by late tomorrow, placing ECFL in an
increasingly favorable divergent upper level pattern, while deep
layer moisture continues to increase in SE low level flow, as winds
aloft back to SW and south. Mid-high cloud canopy will continue to
stream overhead, with moist/convergent low level flow supporting
showers overnight, mainly along the coast. Increase in moisture/jet
forced ascent will lead to higher (mainly 40-50 pct with 60 far SE)
rain chances areawide. Weakening of the mid level cap plus the cold
temps aloft (-15C at H50) could support an isolated afternoon TS.
For temps, another mild to warm night in store with mins ranging
from the L60s along the coast (M60s barrier islands to the U50s Nw
of I-4. Maxes Tuesday in the M-U70s.
&&
.AVIATION...Continued VFR to high end MVFR-VFR CIGs BKN025-050
tonight. LCL BR psbl FM DAB-MCO-LEE early Tue. Better chance for
showers/TS with heavier precip and lower LCL VSBY reductions (MVFR-
IFR). CIGs mainly BKN025-035.
&&
.MARINE...
Tonight-Tuesday...Winds and seas continue to diminish tonight
and tomorrow as the local pressure gradient weakens. However
peak winds/seas of around 15/6FT will likely necessitate Cautionary
Statement beyond 20NM.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...Small Craft Advisory until 10 PM EST this evening for Sebastian
Inlet to Jupiter Inlet 0-20 nm-Volusia-Brevard County Line to
Jupiter Inlet 20-60 nm.
Dense fog advisory until 12 AM EST this evening for 0-20 nm-
Volusia.
&&
$$
JP/JS
Area Forecast Discussion
National Weather Service Marquette MI
630 PM EST Mon Jan 8 2018
.SHORT TERM...(This evening through Tuesday)
Issued at 415 PM EST MON JAN 8 2018
Water vapor imagery and RAP analysis show a shortwave trof moving
across northern Ontario and the Great Lakes. Blustery w to nw winds
have developed in the wake of associated passing cold front. Aided
by 3-4mb/3hr pres rise nw of Lake Superior, winds are gusting to
gale force over central and eastern Lake Superior and up to 45mph on
the Keweenaw. 850mb thermal trof of around -13C combined with a
pocket of deep layer forcing per q-vectors is currently supporting
sct/nmrs -shsn over eastern Lake Superior into Alger/Luce/northern
Schoolcraft counties. Might be a few flurries over the high terrain
of Marquette/Baraga counties. Otherwise, slightly warmer air mass
farther w and influx of drier air is eroding cloud cover over
western Lake Superior.
Pretty quiet short term period is shaping up for tonight/Tue. Winds
will relax fairly quickly from w to e tonight as upstream sfc high
pres ridge extending from Manitoba to IA shifts e, reaching western
Upper MI late tonight, central Upper MI early morning and the e late
morning. Ongoing -shsn off eastern Lake Superior will end tonight as
air mass moderates/dries and subsidence overspreads the area. Any
snow accumulation should be under 1 inch. With high pres ridge
reaching the w late tonight, there should be an opportunity for
strong radiational cooling under light/calm wind and clear skies
before mid/high clouds begin to increase. Favored the bias corrected
regional/global GEM guidance for mins as those models typically
perform best with radiational cooling conditions. Interior w
locations should tumble toward 0F. A few spots may slip blo 0F.
With high pres ridge exiting to the e on Tue, southerly return flow
will develop. WAA/isentropic ascent regime will lead to high clouds
intially, and then a band of mid clouds lifting sw to ne across the
aera. A few models generate some pcpn from this ascent, but
antecedant low-levels seem dry enough to prevent pcpn from reaching
the ground. Should some -sn or flurries develop, probably wouldn`t
last more than an hr. Expect high temps in the mid 20s to around
30F. Although chilly in the morning, won`t feel too bad with only a
very light wind or calm conditions for most locations.
.LONG TERM...(Tuesday night through Monday)
Issued at 240 PM EST MON JAN 8 2018
Upper air pattern consists of a 500 mb trough in the western U.S.
00z Wed with a closed low in the ern Gulf of Mexico and zonal flow
across the north central U.S. The trough in the western U.S. moves
into the plains 00z Thu and affects the upper Great Lakes 00z Fri.
Deep moisture and 850-500 mb q-vector convergence move into the area
late Wed night and last through Thu. Did not make too many changes
to the going forecast overall. Still looks like there could be
advisory level snow for the west Wed night into Thu.
In the extended, GFS and ECMWF show a closed 500 mb low over the
lower Mississippi River Valley 12z Fri with troughing over the upper
Great Lakes then too. Cold air moves in for Sat with lake effect
snow showers cranking up again as an upper trough moves into the
upper Great Lakes 12z Sat. This trough remains into Mon with the
cold air remaining over the area and prolonged lake effect snow
shower again. Temperatures will be below normal for this forecast
period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 628 PM EST MON JAN 8 2018
VFR conditions and light winds are expected at all terminals
overnight thru Tue afternoon. The only exception may be this evening
as a bit of lingering low-level moisture may allow for brief MVFR
ceilings, mainly at KSAW, but KCMX may see these lowered ceiling
develop briefly late this evening.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 415 PM EST MON JAN 8 2018
Some periods of gale force winds expected over the next week with
heavy freezing spray likely Thu/Fri and Sat. Ongoing w to nw gales
over the e half of Lake Supeior will diminish this evening. Winds
will then become light, under 15kt, from w to e late tonight/Tue
morning as high pres ridge passes across Lake Superior. In the wake
of the high pres ridge, winds will ramp up to 20-30kt Tue night/Wed
with at least some gale force gusts over the e half of the lake late
Tue night/Wed morning. Winds will diminish for a time later Wed into
Wed night as cold front drifts over the lake. Winds will then ramp
up w to e late Wed night thru Thu as much colder air drops into the
area behind low pres that moves along the front. Gales will be
possible over central and eastern Lake Superior. Brisk winds will
linger into the weekend as arctic air moves across the Upper Lakes.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
Gale Warning until 10 PM EST this evening for LSZ243>245-248>251-
264>267.
Lake Michigan...
None.
&&
$$
SHORT TERM...Rolfson
LONG TERM...07
AVIATION...KEC
MARINE...Rolfson
Area Forecast Discussion
National Weather Service Blacksburg VA
952 PM EST Mon Jan 8 2018
.SYNOPSIS...
Low pressure area bringing wintry precipitation to the region
will exit eastward through tonight. High pressure will then
build into the region on Tuesday, bringing dry conditions and
warmer temperatures. Cloudy skies then develop as wedge
conditions build in for Wednesday into Thursday. The next chance
for significant precipitation is expected Friday into the
weekend. Temperatures will trend above normal Tuesday through
Friday before trending below normal for the upcoming weekend.
&&
.NEAR TERM /THROUGH TUESDAY/...
As of 948 PM EST Monday...
Expect a diminishing trend to the precipitation through midnight
but will see lingering drizzle/freezing drizzle/light rain/light
freezing rain and/or snizzle over the western slopes overnight.
Having collaborated with neighboring WFOs will handle in
residual ice and hazardous travel with a Special Wx Statement
once the winter weather advisory expires at midnight.
Despite air temperatures above freezing, we have had reports of
slick roads/parking lots and sidewalks especially in SE WV and
SW VA even with air temperatures of 35 to 38 degrees.
We should see temps stay steady-state for the most part
overnight with clouds lingering. Will also be dealing with fog
dense at times in the mountains. This will add to the terrible
driving conditions.
Previous discussion from early evening...
Trimmed back the winter weather advisories in the west and in
the south where the threat for widespread icing problems has
ended. In the south, temperatures have climbed above freezing
and precipitation (freezing rain ) is spotty in nature or has
ended. In the west, mixture of snow,sleet and freezing rain is
tapering off and portions of the winter weather advisories
were allow to expire or were canceled. HighRes models, HRRR and
Highresw-ARW East showed most of the precipitation ending by
03z or 04z tonight. For the remainder of the winter weather
advisories will leave up for now with reports of icing with
colder pockets and will adjust if early cancellation is
warranted. Modified temperatures with latest surface obs,trends
and shaped towards GLAMP. Adjusted weather for late evening into
tonight. Will make more adjustments later tonight...
As of 340 PM EST Monday...No changes or additions were made
with Winter Weather Advisories with the afternoon package.
Though these remain valid, some of these Advisories may be
expired early pending trends this evening.
Current radar shows steadiest precipitation just making it into the
eastern slope of the Blue Ridge foothills westward into the the
Alleghany Highlands/Greenbrier Valley. Precipitation types have been
mostly rain, freezing rain or ice pellets. Despite air temperatures
near or above freezing in this precipitation shield, recent spotter
reports indicate that there are slick spots as far east as Amherst
County. With the pavement being cold, even light rain could become
slippery if falling on untreated roads or sidewalks. Though the
eastern end of the precipitation shield is expected to make it
eastward into the Piedmont by late this afternoon, temperatures from
Rockingham County eastward are currently well above freezing. The
eastern extent of the Winter Weather Advisory, from Rockingham
County through Pittsylvania, Campbell and Appomattox Counties is
quite marginal. In addition, recent trend in higher-resolution
guidance indicates an earlier end to precipitation, perhaps by 01z/9
pm. Will leave this and the other Advisory areas going for now and
will let trends dictate this evening if an early cancellation is
warranted. Would expect an additional trace to 0.05" of ice
accretion with impact again restricted to travel versus power
outages or weighted-down trees. After midnight, any residual Chance-
ish PoPs turns more of an west-northwest upslope character along the
far western mountains. Should also see some gradual decrease in
cloud cover mainly in the Piedmont to the Blue Ridge. Will see lows
tonight in the 30s, except upper 20s in northern Greenbrier county.
For Tuesday, will build high pressure in from the north. This will
lead to drier conditions and a much-welcomed warm-up. Likely to
continue to have lingering stratus clouds into the morning/early
afternoon in the western and southwestern areas that will keep
temperatures down somewhat. By Tuesday afternoon, would expect most
areas to see enough sunshine to push temperatures into the mid 40s
to lower to mid 50s, warmest in the VA Piedmont. Light to calm winds
becoming light easterly late in the day.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 340 PM EST Monday...
Zonal flow over the Mid Atlantic region with slight 500MB height
rises Tuesday night through Thursday. Surface high pressure over the
region Tuesday through Thursday. As the high moves offshore, region
will be in area of broad southwest low level winds between the high
and low pressure over the Ohio and Tennessee Valleys. Enough of a
southeast component to the winds to hold in low level moisture
Wednesday and Thursday. Will be increasing cloud cover both these
days. Staying closer to warner MAV guidance for Tuesday night. Also
slightly below guidance for maximum temperature on THursday with all
the clouds expected.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 340 PM EST Monday...
Starting out with an upper low closing off in the southern stream
over the southern plains then lifting northeast Friday and Friday
night. Canadian was the slowest and GFS the fastest with track of
the surface low. Either way by Saturday afternoon it will be heading
into New England. Broad upper troughing is expected in the eastern
United States Sunday and Monday. 850 MB temperatures rise into the
+10 to +12 range ahead of the low (10 to 20 degrees above normal)
then drop back below zero on Saturday night with another surge of
much colder air (10 to 20 degrees below normal)on Sunday and Monday.
Will have rain in the forecast for Friday and Friday night, changing
to snow Saturday and Saturday night. Too early to pin down any other
kind of winter precipitation. Will be increasing wind speeds and
gusts on Saturday and Saturday night based on combination of strong
cold air advection, 40 knot low level jet and decent pressure
rises.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
As of 635 PM EST Monday...
A wintery mixture of sleet, freezing rain and rain will
gradually taper off from west to east by 03z. Exception is at
Lewisburg where wintry precip may linger through 06z before
tapering dry.
As conditions improve to VFR elsewhere after 05z, will see
areas of IFR- LIFR stratus/patchy fog impacting mainly Bluefield
and Blacksburg. Upslope-type stratus may linger through Tuesday
morning at these TAFs but conditions should generally trend VFR
elsewhere after 05z. Winds south 4-8 kts, with speeds lowering
and veering slightly to west tonight. Winds Tuesday initially
west 3-5 kts becoming light/variable.
Medium confidence on ceilings, visibilities and winds expected
during the taf period.
NOTAM...A complete ASOS surface observation from KDAN
(Danville, VA) is unavailable due to a system processor failure.
The Altimeter is OK, but the remaining instrumentation is OTS.
Parts for the ASOS have been ordered with an ETA of Tuesday.
Extended Discussion...
VFR conditions Tuesday afternoon through evening. Weak wedge
develops by Wednesday with possible sub- VFR in low clouds
across much of the region Wednesday into Thursday. Potential for
wet weather with sub-VFR increases Friday and Saturday.
&&
.EQUIPMENT...
As of 545 AM EST Monday...
A complete ASOS surface observation from KDAN (Danville, VA) is
unavailable due to a system processor failure. The Altimeter
is OK, but the remaining instrumentation is OTS. Parts
for the ASOS have been ordered with an ETA of Tuesday.
Several stream and river gages have been reporting bad data.
This is due to ice affecting the gage. Most of these gages
have been deactivated on our web page, but new ones continue
to appear. We will address this as they appear. We apologize
for any inconvenience the bad data may cause.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...Winter Weather Advisory until midnight EST tonight for VAZ011-
013-014-016>020-022>024-032>035-043>046.
NC...None.
WV...Winter Weather Advisory until midnight EST tonight for WVZ044-
507-508.
&&
$$
SYNOPSIS...AL
NEAR TERM...AL/KK/WP
SHORT TERM...AMS
LONG TERM...AMS
AVIATION...AL/KK
EQUIPMENT...PM
Area Forecast Discussion
National Weather Service Shreveport LA
1004 PM CST Mon Jan 8 2018
.DISCUSSION...
The back edge of low stratus clouds continue to slowly retrograde
westward from AR/LA into NE Texas. This trend will continue during
the overnight hours with areas of fog also expected to develop as
dewpoint depressions bottom out after midnight. For this evening
update, have adjusted cloud cover and overnight low temperatures
accordingly based on the latest trends. Overall, these changes are
not expected to make much difference in the previous forecast
wording. However, will go ahead and issue new text products with
overnight wording. No additional forecast updates are needed at
this time.
/19/
&&
.PREV DISCUSSION... /issued 520 PM CST Mon Jan 8 2018/
AVIATION...
Current Vis Satellite showing the cloud clearing line from just
west of TXK to west of SHV to just east of LFK. A low level ridge
axis will drop southward into the lower Ohio and Tenn Valley and
this will allow 1-3kft winds to become more ENE. This should allow
the MVFR ceilings currently encompassing the TXK/SHV terminals to
retrograde back to the west this evening into the overnight hours.
Meanwhile, dealing with much lower MVFR ceilings at the MLU
terminal with IFR conditions now encompassing the ELD terminal.
The million dollar question is what kind of VSBY concerns will we
have overnight with the possibility of lowering stratus where we
currently have cloud cover and lowering VSBYS as well across our
NE TX terminals with the cloud cover expected to move back in
later this evening. The HRRR suggests the best possibility of
dense fog will develop just west of our western most terminal
locations but for the 00z TAF package, will continue the direction
of the previous TAF package and gradually lower VSBYS across all
terminals overnight with the possibility of dense fog after
midnight through the mid morning hours on Tue. If we see the dense
fog, would of course expect to see VLIFR ceilings as well with
the fog and low ceilings struggling to recover through the morning
hours on Tue.
13
PREV DISCUSSION... /issued 348 PM CST Mon Jan 8 2018/
DISCUSSION...
Clouds continue to hold across much of the region this aftn.
Clouds fcst to hold their ground and even build back wwd tonight,
as sly flow begins to return at the sfc and swly flow aloft sets
up ahead of an upper trof. Moist soils and relatively small
temp/dew point spreads will likely lead to some patchy fog across
much of the region around sunrise Tuesday.
Upper trof just off of the CA coast will move onshore early Tue,
bringing that above-mentioned swly flow aloft as it approaches our
region. Despite the clouds, we will begin to warm up as we head
towards mid week, and temps will reach into the mid and upper 60s
for Wed/Thu. Trof to bring shwrs by late Wed into Thu, with more
widespread shwrs expected by Thu aftn as the associated cold front
moves through. Previous model runs indicated a very slow exit to
moisture in the wake of the front, allowing for some wintry
precip. The latest runs, however, appear to be much warmer and
quicker with the dry-out and are therefore indicating all-liquid
precip. Past experience indicates that this is the most likely
scenario, but we will continue to monitor future trends.
Euro/Canadian solutions show a more srn upper low track than the
GFS, which allow the moisture to linger into Fri. Have split the
difference for now with regard to PoPs, but again, future trends
will bear monitoring.
Very cold airmass in the wake of the late-week cold front will
send our temps plummeting back down to well below normal Friday
through into early next week, and nwly flow aloft will keep us
dry through the end of the pd.
/12/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 42 56 47 66 / 0 10 10 10
MLU 43 55 48 66 / 10 10 10 10
DEQ 35 53 44 62 / 0 10 10 10
TXK 39 52 46 63 / 0 10 10 10
ELD 39 53 45 64 / 0 10 10 10
TYR 40 58 46 66 / 0 10 10 10
GGG 41 57 46 65 / 0 10 10 10
LFK 42 60 46 66 / 0 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
19/13/12
Area Forecast Discussion
National Weather Service Tulsa OK
910 PM CST Mon Jan 8 2018
...UPDATE...
.DISCUSSION...
T/Td spreads have tightened up across northwest AR and far
northeast OK...with low clouds making some westward progress
across northwest AR at the moment. HRRR seems to have a
reasonable handle on this...with lowering visibilities expected
into the overnight hours. Plan on leaving the current dense fog
advisory as is for now and will continue to closely monitor.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 32 53 44 60 / 0 0 0 0
FSM 32 52 40 61 / 0 0 10 0
MLC 33 55 45 60 / 0 0 0 0
BVO 28 53 42 60 / 0 0 0 0
FYV 30 49 44 56 / 0 0 0 0
BYV 32 49 42 58 / 0 0 0 0
MKO 31 53 41 60 / 0 0 0 0
MIO 30 51 41 59 / 0 0 0 0
F10 32 54 44 60 / 0 0 0 0
HHW 35 53 43 62 / 0 0 0 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...Dense Fog Advisory until 9 AM CST Tuesday for OKZ055>058-061>063-
068-069.
AR...Dense Fog Advisory until 9 AM CST Tuesday for ARZ001-002-010-011.
&&
$$
SHORT TERM...18