Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/05/19
AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
954 PM EST Mon Mar 4 2019
A weak trough will track across the region tonight, then weak
low pressure will track east northeast and out to sea Tuesday
into Tuesday night. Cold high pressure then builds back into and
over the region Tuesday night through Wednesday.
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 950 PM EST Monday...
Strong ~980mb low pressure is located new Newfoundland this
evening, with the associated cold front now well off the east
coast. Meanwhile, a 1034mb arctic high is centered over the
central and southern plains.
mostly cloudy to overcast over the Ches. Bay and
northern/central coastal waters this evening. This appears to
be associated with the combination of a weak sfc trough and a
low- level theta-e axis, which is lingering across the local
area. Moisture is proving to be too shallow to yield any pcpn,
and hi-res guidance has backed off with bringing any measurable
PCPN to the coastal zones this evening. Accordingly, have
dropped PoPs for the overnight, though a quick sprinkle or
flurry cannot be completely ruled out over the next 2-3 hours
from the middle peninsula to the VA eastern shore. Temperatures
have already dropped into the upper 20s to low 30s where sky
has remained mainly clear out in the piedmont and over MD zones
of the eastern shore. Therefore dropped temps a bit away from
the Bay and coastal zones where clouds will linger overnight.
Look for overnight low temperatures to range from the low-mid
20 NW to low 30s SE.
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
As of 400 PM EST Monday...
The srn stream low/shortwave trough slides ENE off the coast
Tuesday. Partly sunny N to mostly cloudy S. The 12z GFS is most
aggressive at bringing some light rain nwd into NE NC/far SE VA,
but given rather dry conditions PoPs are ~20% at most, mainly
for light rain, but a brief light rain/snow mix is possible
early. Highs Tuesday will range from around 40F over the Lower
MD/VA Ern Shore, to the lower/mid 40s inland W of the Chesapeake
Clearing and cold Tuesday night, as the modified arctic high to
the west begins to shift east. Lows will mainly range from the
upper teens to the mid 20s. Although below normal, not to record
values (see climo section below). Mostly sunny but unseasonably
chilly Wednesday. Highs only range from the mid 30s to around
40F. Coldest night will be Wednesday night, as the ridge axis
approaches from the west. Lows range form the upper teens to
lower 20s, mid 20s SE coast. Again, not to record values. Mostly
sunny and continued cool Thursday with highs in the low/mid 40s
(upper 40s far S).
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 330 PM EST Sunday...
Weak shortwave aloft (coupled w/ a weakening area of sfc low
pressure) approach the area from the W Thu night-Fri. Still some
disagreement in the models regarding the onset of light pcpn
Thu night. GFS continues to show -SN entering the W/NW Piedmont
after 06z Fri before pcpn overspreads the entire area from W to
E between 12-18z Fri. The ECMWF/CMC are forecasting the pcpn to
hold off until the midday-aftn hours on Fri. The ECMWF/CMC
scenario would result in mainly RA throughout the area (with a
RA/SN mix possible N/NW at the onset of the event). Continued to
go with a consensus of the models, which would suggest a light
RA/SN mix across the N/NW with -RA elsewhere (w/ all pcpn
changing to RA after 15z Fri). Kept PoPs aob 30% through 18z
Fri. Models are more in agreement that -RA will continue
throughout the area from Fri aftn-late Fri evening (especially
south/east). Still some uncertainty about the exact timing, so
kept PoPs aob 50% from 18z Fri-06z Sat. Drying out by 12z Sat as
the weak low pressure system moves offshore and a weak cold
front stalls just S of the CWA. Lows Thu night range from the
upper 20s NW to the mid-upper 30s SE. Highs Fri range from the
mid 40s NW to the low 50s S/SE.
Dry (and near average) on Sat as weak upper ridging briefly
moves over the ern CONUS. A strong area of low pressure tracks
from the Plains to the Great Lakes from Sat-Sun. This will allow
the cold front that stalled just south of our CWA to move back
N as a warm front on Sat night-Sun AM. The warm front will
quickly surge N of the CWA by midday Sun. Showers are expected
to overspread the area from W to E Sun AM. Heavier showers will
be possible from Sun aftn- Sun evening as the associated cold
front approaches from the WNW. Models are hinting at some sfc-
based instability Sun aftn/evening from srn VA to NE NC as
temperatures could warm up to near 70 in spots (as dew points
rise to near 60). Did not add thunder to the grids attm, but may
need to do so in upcoming forecast packages. Drying out late
Sun night-Mon as the cold front clears the area. The airmass
behind the front will not be as cold as the one that is progged
to enter our area during the middle of this week. Highs on Sat
are expected to be in the 50s to near 60 in most areas. Forecast
highs on Sun range from the upper 50s N/NW to the mid-upper 60s
over SE VA/NE NC. Highs still in the upper 50s-mid 60s on Mon.
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
As of 630 PM EST Monday...
Weak low pressure is centered just to the E of RIC early this
evening as an area of CU/SC (~4-5k feet) extends from central
VA to NE NC. Some of the hi-res guidance continues to show a
small area of very light pcpn developing over east-central VA
between now and 03z. However, the latest runs of the HRRR keep
the area dry (so confidence in the pcpn developing is low-
moderate). If this area of pcpn forms, it will slowly drop SSE
into SE VA through 03-06z, before dissipating thereafter. This
should mainly be light rain, although a light rain/snow mix is
possible. Removed any mention of pcpn from RIC, but kept VCSH in
the TAFs for ORF/PHF. CIGS should mainly be around ~4k feet,
although brief MVFR CIGS are possible later this evening into
the early overnight hours over SE VA/NE NC. Weak low pressure
tracks off the Southeast coast Tuesday bringing additional cloud
cover to the terminals, but VFR conditions are expected to
prevail (CIGS will be in the 3-5k ft range over SE VA/NE NC
through much of the day on Tue). Expect mid-high clouds at
RIC/SBY from late tonight through 18z Tue before SKC conditions
prevail during the remainder of the aftn/evening. Winds remain
aob 12 kt through the 00z TAF period.
Dry and mostly clear/sunny conditions are expected Tuesday night
through Thursday. Another low pressure system approaches from
the W Friday and this could bring unsettled conditions later
Friday into early Saturday.
As of 930 PM EST Monday...
Cancelled SCAs for all ocean zones as seas have fallen to 3.5-4.5
feet as per buoy obs. Seas will continue to slowly diminish
through the remainder of the night.
Improving conditions this afternoon across the marine zones. Winds
have dropped to 5-15 knots in the Bay and 10-20 knots offshore and
will continue to decrease through the evening. Waves are running 1-3
feet and will become 1-2 feet this evening. Seas will be a little
slower to drop with current seas 4-6 feet, becoming 3-5 feet
overnight. SCA headlines remain in effect through late tonight for
the offshore zones but areas south of Cape Charles Light could fall
below thresholds by mid evening as seas subside. Models are picking
up on a subtle NNW surge tonight with winds increasing back into the
~15 knot range for a few hours prior to daybreak. Winds are
forecast to stay below SCA limits and no new headlines are
planned with this package.
Generally quiet marine conditions are expected for the daylight
hours of Tuesday as weak low pressure passes to our south across the
southern Carolinas. A period of enhanced northwesterly flow will
ensue late Tuesday night into Wednesday as a dry cold front crosses
the region and high pressure builds toward the area. Another round
of Small Craft headlines appears likely from late Tuesday night into
early Wednesday afternoon.
As of 345 PM EST Monday...
Despite the level at Sebrell below flood state attm, the
warning will remain in effect based on Sun night`s rainfall
taking it back above flood stage this evening. Otherwise, expect
rises on most rivers over the next few days due to Sun night`s
rainfall. See FLSAKQ for details.
Record low temps:
Wed 3/6 Thurs 3/7:
RIC...15 in 1960 12 in 1960
ORF...20 in 1901 17 in 1899
SBY...13 in 1978 11 in 2015
ECG...20 in 1960 20 in 1960
Record low max temps:
RIC...28 in 1901
ORF...28 in 2015
SBY...31 in 2015
ECG...34 in 2015
Area Forecast Discussion
National Weather Service Caribou ME
1052 PM EST Mon Mar 4 2019
Low pressure will continue to pull away overnight. High
pressure will follow into the region on Tuesday with colder
weather through mid-week.
.NEAR TERM /THROUGH TUESDAY/...
1030 PM Update...
Radar showing last round of snow moving to the east. The latest
HRRR and NAM12 aligning quite well w/the placement. Looks like
steadier snow will be winding down after midnight w/some snow
showers hanging in overnight, mainly across the north and west.
Any additional snowfall accumulation will be < an inch.
Temps were holding up in the 20s across the CWA. Colder air
still residing back across Quebec. Will need the upper trof to
swing across the region to bring that colder air into the
region. This is expected to take place overnight w/temps
dropping off as skies partially clear out.
Once snow mvs into NB, winds turn WNW drawing in cldr dwpt
temps. Skies rmn cldy acrs the north thru most of the ovrngt
with Downeast areas moclr tonight. Temps wl drop into the single
digits acrs the north with low teens for Downeast areas under
fresh snowcover. Highs on Tue wl run about 10 degrees blo normal
with ongoing cold advection.
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
A very cold upper trough will propagate towards the area from
Quebec Tuesday night and will induce weak cyclogenesis in the
Gulf of Maine as another weak surface low in Quebec fills.
There`s very little moisture with this system and it will be
moving across the area rapidly. The developing system could drop
a quick dusting to an inch across the area before it deepens and
picks up more moisture east of Maine. With light winds and
variable cloud cover, lows will be challenging for Tuesday
night. Will lean towards enough clearing to produce some subzero
readings in Aroostook County and single digits to low teens
elsewhere. The cold upper trough will slowly cross on Wednesday
and generate some very steep low level lapse rates. Expect
scattered snow showers to develop by midday and a few could be
fairly heavy. The deep mixing layer to at least H800 could also
produce gusty winds reaching up to 30 mph in the afternoon.
Highs will generally be in the low to mid 20s. Another tough
radiational cooling forecast follows Wednesday night. Unusually
cold air will be in place with subzero temps north and low
single digits elsewhere. With a fairly steady light wind, any
radiation inversion will be very shallow and potentially short-
lived. Nonetheless, a few hours of decoupling in northern
valleys could result in some minus 20F readings. Thursday will
feature highs some 15 degrees below normal as the cold air mass
will be fully in place. There`s just enough H850 moisture for
fair wx cu in the north by midday. Can`t rule out a flurry, but
will not include pops at this point.
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
The cold air mass remains in place into Sunday. For Thursday
night, chances are good for another night of good radiational
cooling. Winds will be lighter than the previous night. Fair
weather continues under high pressure for Friday, but with
southwest winds and warm air advection, highs should be some 7
to 8 degrees warmer than the previous day. On Friday night into
Saturday morning, a weakening cold front will cross. Prefer the
ECMWF and GEMs over the operational GFS for this feature. It
will by a dry front, but did impact the low temp forecast Friday
night with less radiational cooling. Although, there`s good cold
air advection behind the front, surface temps will be warmer on
Saturday as temperatures rise above freezing at Bangor and along
the coast. High pressure crests over the area Saturday night and
have again gone for subzero temps in the north Saturday night.
Clouds will increase on Sunday ahead of a frontal system. A lot
of uncertainties remain regarding this system. The first
question involves the expected southerly marine flow and whether
widespread low clouds will develop over the area Sunday morning.
The next question involves the extent and speed of the warming
aloft and at the surface. In general, the system will be a warm
occlusion in the southern stream overrunning the cold air mass
that has been in place all week. Have taken a compromise between
the warmer GFS and cooler ECMWF. The result brings mixed
precipitation later Sunday into Sunday night. Can`t rule out a
potential advisory in the north, but temperatures will rise all
night and all precip should be in the form of rain by Monday
morning. Monday is shaping up to the warmest day since early
February. The duration of the expected warming does not look
long enough for hydro issues as subfreezing temps return Monday
night. However, the air mass arriving next week is not nearly as
cold as this week.
.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: IFR conditions this afternoon, improving to MVFR
around 20z at BGR and BHB. Northern terminals becoming MVFR
after 00z tonight. Improvement to VFR later tonight into Tue
SHORT TERM: VFR is expected to be the predominant condition from
Tuesday night into Saturday with the exception of a brief
period of IFR vis in snow Tuesday night. Scattered snow showers
with tempo IFR vis are possible Wednesday afternoon...mostly
north and east of BGR and BHB.
NEAR TERM: SCA conditions expected thru Tue morning with wind
gusts aoa 25kts. Expect winds to dip blo for about 4-6 hrs this
evng but increase after 02z. Seas wl rmn above 5ft thru the day
SHORT TERM: Small Craft Advisory conditions are possible
Wednesday into Wednesday night, Thursday night, and Friday into
Friday night. Winds reaching gale strength has to be considered
MARINE...Small Craft Advisory until 1 PM EST Tuesday for ANZ050>052.
Area Forecast Discussion
National Weather Service Jackson MS
855 PM CST Mon Mar 4 2019
Updated for evening discussion and aviation discussion.
Precipitation will end soon over the Pine Belt region as the weak
upper wave pushes quickly east. Have trended down pcpn chances in
the evening forecast, and current trends suggest there shouldn`t
be any additional concern for potential travel issues. Otherwise,
freeze warning remains in effect with strong cold advection
continuing. Temperature at JAN has fallen below freezing as of
early evening, the first time since the end of January, so a long
impactful freeze is expected with temperatures likely not rising
above freezing until mid/late tomorrow morning. /EC/
Prior discussion below:
Have updated the near term forecast again to increase POPs with
precip coverage expanding and now a few CGs being noted by the
lightning network along the Hwy 98 corridor. Continuing to get
reports of sleet and will keep that going for the next few hours.
Sfc wet bulb freezing line is encroaching upon the precip shield
over sw MS and will need to monitor southward movement of this
line closely for potential bridge impacts along the Hwy 84
corridor, but thus far it still looks impacts will be minimal.
This is a fast-moving wave so expect precip to end quickly before
midnight over the Pine Belt region. /EC/
Prior discussion below:
Given recent reports of sleet in the Alexandria, LA to Woodville,
MS area, have added sleet into the late afternoon/evening
forecast, but still expect minimal impacts at most. Latest HRRR
guidance indicates a significant mid level warm nose that should
melt most of introduced ice into that layer, but the sub cloud
cold layer forecast ~ -6 C would support refreeze of liquid into
sleet. With all this said, sfc temps are expected to remain just
above freezing in the precip area and the only concern for impacts
would be with a heavier sleet burst that could still accumulate.
At this time, expecting any accumulating precip to remain south of
the I-20 corridor. /EC/
Prior discussion below:
Tonight and Tuesday:
Continued much colder than normal and mostly dry for our CWA
through the period. The exception to the dry weather will be
across the south later this afternoon and into the early evening
as a weak disturbance aloft moves across the area and squeezes out
some light precipitation. CAA has held temperatures today much
cold than normal. A few spots in our northwest were still below
freezing at 1 PM. Mid afternoon surface analysis had a >1030mb
high centered over the Central Plains. This surface high will draw
a little closer to our CWA tonight and Tuesday. This will allow
temperatures to drop below freezing again by 9PM across the
northwest half of our CWA and the remainder of our CWA shortly
after midnight. Tuesday morning lows are expected to range from
lower 20s north to the upper 20s southeast. Due to an early
growing season, hard freeze warning criteria will be met at most
locations and a Freeze Warning remains in effect tonight into
Tuesday morning. Record lows for the date Tuesday are a couple
degrees colder than forecast lows. There will still be a cold
northwest to north wind Tuesday but skies will be mostly sunny.
This insolation should allow temperatures to warm into the mid to
upper 40s Tuesday afternoon. Normal afternoon highs run from the
lower 60s north to the upper 60s southeast. /22/
Wednesday through the weekend:
Wednesday morning will be the coldest part of this week as the
surface high pressure shifts directly overhead. Low temps will once
again fall into the 20s areawide. A Hard Freeze Warning will be
needed through part of the morning. Once the sun comes up, temps
will rise quickly under clear skies. As the high shifts east,
southerly surface flow moves in and warm, moist air begins to filter
into the region again. Temps will rebound back to normal values by
Thursday. On Friday, a warm front will lift north through the area
and collide over the Mid-South with an upper shortwave trough. This
collision will allow some showers to form and affect the northern
portions of the CWA. Temps will even rise into the 70s in the
southern parts of the area.
Going into Saturday, a deepening trough moves into the central U.S.
The global models still differ in the strength of this system as the
GFS has a cutoff low forming while the ECMWF has an open wave. Both
models still show a strong cold front pushing through the CWA though
in the Saturday night into Sunday timeframe. The severe parameters
are looking pretty good at this point with plenty of instability and
lots of shear. At this point though, we`re not putting any severe
threat into the HWO just yet. We`ll wait and see if the global
models continue to show this strong system and come into better
agreement with the evolution of this system. An outlook may be
needed in the coming days. /10/
18Z TAF discussion:
VFR conditions and NNW surface winds ~ 10kt will prevail through
the forecast period. Sfc wind will be gusty late Tues morning
into afternoon during time of greater boundary layer mixing. /EC/
.PRELIMINARY POINT TEMPS/POPS...
Jackson 25 43 24 53 / 5 0 0 0
Meridian 26 45 24 54 / 7 0 0 0
Vicksburg 26 44 25 50 / 4 0 0 0
Hattiesburg 28 48 26 57 / 30 0 0 0
Natchez 26 44 25 53 / 5 0 0 0
Greenville 25 41 24 45 / 3 0 0 0
Greenwood 24 40 23 48 / 4 0 0 0
MS...Freeze Warning until 10 AM CST Tuesday for MSZ018-019-025>066-
LA...Freeze Warning until 10 AM CST Tuesday for LAZ007>009-015-016-
AR...Freeze Warning until 10 AM CST Tuesday for ARZ074-075.
Area Forecast Discussion...UPDATED
National Weather Service Jacksonville FL
951 PM EST Mon Mar 4 2019
Weak cool advection pattern will continue tonight as strong high
pressure moves to the central U.S. A shortwave trough in the srn
Plains will move quickly to the southeast states late tonight and
Tuesday morning, accompanied by increased moisture field and
strengthened lift. Models have a decent handle on the current light
precip over srn LA to southwest AL, though the NAM seems overly
aggressive with the precip compared to the GFS and HRRR overnight
hours into the morning. The timing of the precip entering the
area is after about 3 am and continuing into the mid to late
morning hours, then pushing east of the area. Not much change to
the elevated rain chances over the area during this time period
with chances ranging from about 40-50 percent over southeast GA to
10-20 percent across the srn most zones. Chance of precip is a
little higher over ern parts of northeast FL in the early morning
hours. Rainfall amounts up to 0.20 inches are expected. Lows
tonight will be in the 40s to lower 50s, with temps being held
back by a blanket of clouds coming in from the west after 1-2 am.
Colder Tuesday with highs in the 50s to lower 60s. Cold advection
and much drier air will filter in Tuesday night into Wed morning
with a possible light freeze. Given MOS guidance, the light
freeze may extend a little further south over north FL.
VFR through late tonight. A disturbance will move across the
region bringing increased clouds and a chance of rain after 08z
and continue through about 15z-16z before moving offshore. Drier
conditions expected thereafter. Some MVFR cigs are possible but
latest guidance not too confident on low cigs below 2000-3000 ft.
Not expected any vsby restriction in the rain at this time as it
moves through early Tuesday. Light winds tonight become west to
northwest near 8-12 kt and gusty to near 20 kt by late Tuesday
morning and afternoon.
Current forecast on track with northwesterly winds of around 10-15
kt and seas up to 2-4 ft. Northerly winds are expected to pick up
on Tuesday and advisory conditions will be possible late Tuesday
.PRELIMINARY POINT TEMPS/POPS...
AMG 40 56 31 53 / 50 30 0 0
SSI 48 58 36 54 / 50 50 0 0
JAX 45 62 36 57 / 40 60 0 0
SGJ 49 62 40 57 / 20 60 0 0
GNV 46 62 36 59 / 30 50 0 0
OCF 49 64 36 60 / 10 40 0 0
FL...Freeze Watch from late Tuesday night through Wednesday morning
for Baker-Columbia-Hamilton-Inland Nassau-Suwannee.
GA...Freeze Watch from late Tuesday night through Wednesday morning
Echols-Inland Camden-Inland Glynn-Jeff Davis-Pierce-Ware-