Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 12/07/19
Area Forecast Discussion
National Weather Service Bismarck ND
632 PM CST Fri Dec 6 2019
.UPDATE...
Issued at 630 PM CST Fri Dec 6 2019
No major changes are needed for this update. The 18Z NAM and
NAMnest want to bring some light freezing rain across far north
central North Dakota tomorrow morning associated with strong low
level warm air advection. Even though the RAP does not generate
any QPF, its BUFKIT soundings support this potential. Will leave
this out of the forecast for now and see if there is greater
consensus and/or consistency with the 00Z suite of guidance.
&&
.SHORT TERM...(This evening through Saturday)
Issued at 201 PM CST Fri Dec 6 2019
Tonight we are expecting some patchy fog to form again over the
persisting snowpack. Overnight lows will be in the teens east to
upper 20s west where there is less/no snow and westerly winds will
a little more persistent.
Saturday should be mild and dry with continued warm air advection
and more robust westerly winds. Temperatures in the upper 40s are
likely across western North Dakota with lower readings east where
snow will continue moderating temperatures.
.LONG TERM...(Saturday night through Friday)
Issued at 201 PM CST Fri Dec 6 2019
The concerns for the long term are the chance for accumulating
snow with a weak clipper system followed by much colder
temperatures next week.
Models and ensembles are coming into better agreement with timing,
placement and amounts of snow for Sunday. It appears snow will
start across northwest North Dakota early Sunday morning. Snow
will slowly shift southward through the day. Initial precipitation
should be rather light with limited ascent and forcing, but
snowfall rates/amounts should pick up Sunday afternoon across
southwest North Dakota when/where more robust ascent and forcing
are expected. There is the potential for some banded snow to
develop with mid-level frontogenesis, moderate lapse-rates and
upper-level ascent. Generally, between two and four inches of snow
is possible from Williston down through Dickinson, Bismarck,
Linton and Ellendale. It is possible some locations across the
southwest could see some isolated higher amounts if a narrow band
of more intense snow does develop.
After the snow ends Monday morning, several arctic high pressure
systems will bring reinforcing shots of cold air into the region
through Thursday morning. High temperatures during this period
will only rise to around zero east to the teens west, and
overnight lows 10 to 15 below zero. Wind chills could fall into
the advisory category of 25 below central and east.
Cold and dry for the week after Monday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 630 PM CST Fri Dec 6 2019
The expectation is that MVFR/IFR stratus will continue across
central into southeast ND through the night, with conditions
gradually improving from west to east Saturday morning. There is
also potential for fog developing across northern, central, and
into southeast ND tonight with IFR to possibly LIFR visibilities.
The MVFR/IFR stratus and potential fog may briefly move over KXWA
this evening and early overnight. Otherwise, western ND terminals
should see VFR conditions through the forecast period. Expect
light winds overnight, becoming west to southwest around 10 kts
Saturday afternoon.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Hollan
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...Hollan
Area Forecast Discussion
National Weather Service Boston/Norton MA
1014 PM EST Fri Dec 6 2019
.SYNOPSIS...
Clearing skies with colder, drier air moving across the region
overnight with high pressure building in from the west. Many
areas will have sub- freezing high temperatures on Saturday,
followed by a frigid Saturday night. The high moves offshore
Sunday, starting a return flow of milder and moist air for the
first half of the week. This will bring off and on rain for
Monday and Tuesday. A cold front moves through Tuesday night,
and there might be some back-end snow on Wednesday although
confidence is very low at this point. We dry out by late
Wednesday and return to colder than normal temperatures for
early December on Thursday.
&&
.NEAR TERM /THROUGH TONIGHT/...
1005 PM update...
All precipitation has exited the region. Skies were becoming
mostly clear over most of the region. Low pressure was centered
off of Cape Cod with high pressure building eastward from the
eastern Great Lakes region. The gradient between the two was
causing some very gusty winds...Worcester/Willimantic/Windsor
Locks were all gusting to 26 kt (around 30 mph) during the past
hour. These winds are forecast to only be brief, until the air
gets colder and the boundary layer decouples. Have combined the
RAP wind gusts with existing grids to arrive at wind gust
forecast. This has necessitated extending the Small Craft
Advisories for Boston Harbor and Narragansett Bay through the
night. Overnight lows should reach the teens to lower 20s, with
mid 20s to lower 30s Cape Cod and the Islands.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
Saturday colder and drier air pours into the region as high
pressure builds in, though cyclonic flow lingers aloft.
Subsidence under this high will keep things dry and skies mostly
clear. Diurnal cumulus should develop given a cyclonic flow set
up with cold air advection and daytime heating. Much of the
area would see sub-freezing highs, with the interior higher
elevations only reaching the upper 20s. Low to mid 30s near the
coast. Albedo effect from snow cover would also negate daytime
heating.
On Saturday night, a combination of light winds and mostly
clear skies should allow temperatures to drop even more quickly
than the previous night. A few locations in the interior higher
elevations could even see single digit lows. Elsewhere,
widespread teens are expected and 20s on the coast.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
Highlights...
Cold start to Sunday before temperatures rebound during the
day.
Rain spreads in early next week with temperatures trending upward.
Potential for strong winds on Monday and Tuesday especially across
eastern MA.
Temperatures trending downward on Wednesday and Thursday.
Possibility of snow as precipitation is ending on Wednesday.
Daily Concerns...
Sunday...
Cyclonic flow initially with a mid level ridge building over the
eastern Great Lakes. A trough will lift off to the northeast and the
ridge will slide in over New England. This will bring clear skies
and very light winds with the high overhead. Still have high
confidence in strong radiational cooling. Knocked down temperatures
toward the 25th percentile of guidance. Held off from the 10th
percentile because it seemed too cold along the coastline given
there may be some clouds exiting. Nudged down temperatures a bit
further in the typical cold spots. Overnight lows range from the
single digits above zero across the Berkshires and I-495
west corridor to the mid 20s across Cape Cod.
The ridge axis shifts off to the east on Sunday which shifts flow
aloft to a southwesterly direction and advects warm air into the
region. This will trend temperatures upward during the day. Expect
partly to mostly sunny skies with highs ranging from the low 30s
across northwest MA to the low 40s along the coast. High confidence
in the forecast during this period.
Monday and Tuesday...
Pattern change underway with zonal flow shifting to a more amplified
flow. Models have come into agreement with a northern and southern
stream trough digging in from the west. The weaker southern stream
trough will dig into the desert southwest on Monday while the
northern trough digs into the Northern Plains and western Great
Lakes. As the trough digs into the western Great Lakes several
shortwaves will ripple along the central and eastern Great Lakes.
This will provide lift along with a warm front and spread rain into
the region. Still seeing a strong 40 to 70 kt low level jet develop.
This continues through Tuesday with the low level jet shifting to
the east. The GFS and ECMWF have come into good agreement, but still
uncertain how much of these winds will translate to the surface. Did
bump up speeds and gusts with gale force gusts anticipated across
the coastal waters late on Monday into early Tuesday. If we tap more
into the low level jet speeds then winds will need to be increased
further. There will also be some instability present and suspect
that there will be a few rumbles of thunder, but confidence in
particular timing and placement is low at this time. It will be much
warmer with high temperatures in the 50s on Monday and Tuesday.
Suspect that there will be some 60 degree readings on Tuesday. Could
see a good slug of precipitation with GEFS QPF still quite spread
out with amounts between 0.75 to 3.0 inches when it is all said and
done. Will be worth keeping an eye on for future updates. Low to
moderate confidence in the forecast for this time frame.
Wednesday and Thursday...
Precipitation coming to an end on Wednesday. Overall there is pretty
good agreement amongst guidance synoptically, but the ECWMF holds
onto heavier precipitation longer than the GEM and GFS. If the ECMWF
holds true there could be some snowfall accumulation, but confidence
at this point in time is very low. Do have high confidence in the
colder air moving in as the trough lifts to the northeast.
Temperatures will be trending downward with readings in the low 30s
across the west on Wednesday and in the low to mid 40s across the
coast and east. Temperatures will be colder on Thursday with highs
ranging from the mid 20s across the Berkshires and Worcester Hills
to the low 30s along the coast. Moderate confidence in the cooler
temperatures, but low confidence in weather expected on Wednesday.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Short Term /through Saturday Night/...High confidence.
0305Z update...
Tonight...Local IFR/MVFR in eastern MA until 05Z-06Z. Otherwise
VFR most areas. W-NW winds increasing to 25-30 kt in gusts
briefly, for a couple of hours, then diminishing late.
Saturday...VFR. Light NW winds.
KBOS Terminal...High confidence in TAF. IFR becoming VFR before
06Z. Wind gusts to 25 kt expected, diminshing by daybreak.
KBDL Terminal...High confidence in TAF.
Outlook /Sunday through Wednesday/...
Sunday: VFR. Breezy.
Sunday Night: Mainly VFR, with local MVFR possible. Windy with
local gusts up to 30 kt. Slight chance SHRA.
Monday: Mainly MVFR, with areas IFR possible. Windy with local
gusts up to 30 kt. SHRA likely.
Monday Night: Mainly MVFR, with areas IFR possible. Windy with
gusts up to 35 kt. SHRA.
Tuesday: MVFR. Windy with gusts up to 30 kt. SHRA likely.
Tuesday Night: Mainly MVFR, with areas VFR possible. Breezy.
Chance SHRA.
Wednesday: Mainly VFR, with areas MVFR possible. Breezy. Slight
chance SHRA.
&&
.MARINE...
Short Term /through Saturday Night/...High confidence.
1005 PM update...
Overnight... Have extended the Small Craft Advisory for Boston
Harbor and Narragansett Bay through 4 AM because winds were
becoming gusty between departing low pressure and approaching
high pressure. Have also increased seas to 4 ft on Nantucket
Sound based on reports from the Steamship Authority. NW winds
gusting to 25-30 kt nearshore and 30-35 kt offshore, slowly
diminishing late. Seas 3 to 6 ft except 8 to 10 ft on the
southern outer waters.
Saturday... Clear skies and light winds. Seas 3 to 5 ft.
Outlook /Sunday through Wednesday/...
Sunday: Winds less than 25 kt.
Sunday Night: Low risk for Small Craft Advisory winds with
gusts up to 30 kt. Seas up to 5 ft. Slight chance of rain
showers.
Monday: Low risk for Small Craft Advisory winds with gusts up
to 30 kt. Local rough seas. Rain showers likely.
Monday Night: Strong winds with gusts up to 35 kt. Rough seas
up to 13 ft. Rain showers likely.
Tuesday: Strong winds with gusts up to 30 kt. Rough seas up to
13 ft. Rain showers likely.
Tuesday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Rough seas up to 11 ft. Rain showers likely.
Wednesday: Low risk for Small Craft Advisory winds with gusts
up to 25 kt. Rough seas up to 10 ft. Chance of rain showers.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 11 AM EST Saturday for ANZ231>235-
237-250-251.
Small Craft Advisory until 4 AM EST Saturday for ANZ230-236.
Small Craft Advisory until noon EST Saturday for ANZ254.
Gale Warning until 1 AM EST Saturday for ANZ255-256.
&&
$$
SYNOPSIS...Field/BL/Chai
NEAR TERM...Field/Frank/Chai
SHORT TERM...Frank/Chai
LONG TERM...BL
AVIATION...Field/BL
MARINE...Field/BL/Chai
Area Forecast Discussion
National Weather Service Grand Junction CO
452 PM MST Fri Dec 6 2019
.SHORT TERM...(Tonight through Saturday night)
Issued at 223 PM MST Fri Dec 6 2019
Quiet and dry weather will continue this afternoon, as the ridge of
high pressure moves overhead. A deck of high clouds will continue to
stream across the region this evening, with lower clouds lingering
across the north. Some clearing is likely tonight, while winds aloft
transition to west-southwest flow.
Low level clouds and fog will likely develop again across
northeastern Utah and western Colorado Saturday morning. Light winds
at the surface combined with lingering low level moisture will
support fog forming across the Gunnison and Yampa Valleys, portions
of the Grand Valley, and near the Uinta Basin. Patchy areas of fog
will quickly clear after sunrise; however, other regions with a more
consistent stratus deck aloft (such as Gunnison and Vernal) may
experience poor visibilities and low cloud ceilings persisting into
afternoon hours.
Expect winds to shift towards the west Saturday afternoon, as upper
level flow turns zonal ahead of the next system. Zonal flow
accompanied with increased winds aloft will briefly improve mixing
at low levels for most of western Colorado and eastern Utah. Areas
with decent mixing will result in slightly warmer temperatures and
could see stronger winds reaching the surface. Mixing should also
help conditions improve across areas with lingering low level clouds
and morning fog. Otherwise, weather conditions will remain dry
across the region into Saturday evening, however cloud clover will
begin to spread across the region ahead of the next system. Chances
for precipitation also increase late Saturday night, mainly over
higher terrain, while the rest of the region will experience mild
overnight lows due to the insulation from a blanket of cloud
cover.
.LONG TERM...(Sunday through Friday)
Issued at 223 PM MST Fri Dec 6 2019
Precipitation will break out over much of the higher terrain of
eastern Utah and western Colorado early on Sunday morning. The
trough responsible for the unsettled weather is not particularly
strong, but it will make up for this with a broad shield of
moisture and favorable westerly upslope flow through the day on
Sunday. A diffuse frontal boundary does pass east through the
western slope on Sunday afternoon as well, with 700mb temperatures
dropping 2-4 degrees across the board by the end of the main
event on Sunday evening. This will help snow ratios, especially
in the central and northern mountains. Latest QPF guidance in the
12z forecast cycle today showed a slight uptick in precipitation
totals, with snow totals possibly exceeding 6 inches in the Park,
Flat Top, Gore and Sawatch ranges. Farther south in the Elks and
San Juans, close to 1" of liquid is forecast by some
models...which could result in nearly a foot of snow in favored
westerly and northwesterly slopes. Lower elevations are a bit more
tricky, as snow levels and warm air in the valleys will play a
role in Precipitation Type early in the event. If enough cold air
filters in on Sunday afternoon, an inch or so will be possible in
places like Craig, Rifle and Montrose, with 1-3 inches in
Steamboat (town), Vail, and Gunnison. The US160 corridor is a
particularly challenging forecast, as the San Juan Mountains may
block the progress of much of the colder air from the north.
Durango could easily see 0" in this case, however a slushy inch or
so in the grass is also possible if colder air makes it in before
precipitation ends Sunday evening.
The trough axis with this system passes east of the Continental
Divide by early Monday morning with flow turning northwesterly
over eastern Utah and western Colorado. A shallow stream of
moisture will remain in place over the northern Colorado mountains
in this northwest flow pattern from Monday through Tuesday
morning. Favorable upslope flow will result in additional snow
accumulations in the northern Parks and Elkhead mountains, however
model consistency has not been high in this timeframe. Things
finally dry and clear out on Tuesday evening up north as a ridge
builds in over the Four Corners for Wednesday. Both the ECMWF and
GFS indicate a weak, dry trough moving through on Thursday
resulting in a mainly cloudy day. The next opportunity for
precipitation will arrive by Friday morning as a fast Pacific jet
moves inland and into the Great Basin. Both the ECMWF and GFS
support the idea of unsettled weather from Friday into Saturday
however specific details with this system will have to wait for
better model consistency on both temperatures and the position of
the best moisture stream.
Overall, forecast confidence is moderate throughout the long term.
Winter weather headlines will likely be needed in the mountains for
the storm arriving on Sunday morning, and will be addressed in
forthcoming forecast packages.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 445 PM MST Fri Dec 6 2019
Mid level ceilings around 4K to 5K feet persist over the northern
valleys at this hour and cross sections suggesting this will
continue through the overnight. HRRR data thinks otherwise though
as RH values drop off significantly. Satellite data showing some
movement to the low clouds so gave the nod to the HRRR with some
clearing over the next few hours. KVEL will likely come back down
though as dewpoint depressions are very similar to yesterday when
fog dropped the airport to 1 1/2 miles and ceilings near 200 feet.
Outside of those areas, expect some high clouds especially down
south.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...None.
UT...None.
&&
$$
SHORT TERM...ERW
LONG TERM...MAC
AVIATION...TGR
AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
943 PM EST Fri Dec 6 2019
.SYNOPSIS...
High pressure and a drier, seasonable air mass will build into
the region for the weekend. A low pressure system will lift up
across the Great Lakes region Sunday night into Monday, bringing
another chance of precipitation to start off the work week.
&&
.NEAR TERM /THROUGH SATURDAY/...
Northerly winds are continuing to usher drier air into the
region through the boundary layer, with clouds now limited to
just the far southern tier of ILN counties, and soon to exit the
area entirely. Outside of some streaks of cirrus moving
southeast through the Great Lakes, skies are expected to be
clear overnight, with winds generally becoming light. This has
allowed for temperatures to drop significantly already, with
several locations (including the NWS office) already reaching
the upper 20s. The min temp forecast (mid to lower 20s) still
looks mostly good, but some outlying areas may even drop a
couple degrees further than that. Comparing to current numbers,
the 01Z RAP looked most reasonable, and was used as a basis to
adjust the grids for this evening update.
Previous discussion >
A cold front moving through the area today has resulted in a
concentration of light rain primarily south of I-70 with
sprinkles to the north. Any remnant showers clear the southeast
by late this afternoon with scattered stratocumulus remaining
through the evening. Clouds clear overnight and temperatures
cool into the mid to lower 20s area wide as surface high
pressure builds in from the northwest.
&&
.SHORT TERM /SATURDAY NIGHT/...
Surface high pressure moves east across the region during the
day on Saturday. This leads to mostly clear skies and dry
conditions. Winds are forecast to be weak and temperatures will
be seasonable with highs on Saturday in the low to mid 40s.
Upper level clouds stream in from the northwest late in the day
but nighttime low temperatures are still expected to drop into
the lower 30s (west) and upper 20s (east).
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
The region will be in southwest low level flow at the beginning
of the extended as the area is located between a retreating
high pressure center located over the east coast and a cold
front in the western Great Lakes into the plains.
With the southerly flow, broad isentropic lift will begin to
affect the region on Sunday. The NAM continues to produce the
light rain showers across the area, while the operational GFS
and ECMWF keep the region dry. Will keep continuity and will
have a 20 PoP on Sunday only for the Cinci Tri-State.
Sunday night into Monday an approaching cold front will
increase the lift and rain will become more widespread. Highs
Sunday and Monday will be in the 50s as the region is on the
warm side of the front.
Models are still showing some minor differences in the strength
and location of the surface low that is driving the cold front.
However, they are in pretty good agreement on the timing of the
frontal passage. General consensus is that fropa will be late
Monday night. With a strong arctic airmass behind the front, it
is looking like temperatures will fall on Tuesday. A change over
from rain to snow will accompany the change in airmass. With
the strong cold air advection will linger flurries Tuesday into
Tuesday night.
Well below normal temperatures are forecast for Wednesday as
the arctic high builds into the region. Morning lows will be in
the teens to lower 20s Wednesday morning, and highs will only
recover into the mid 20s to lower 30s in the afternoon.
On Thursday the center of the high will slide off to the east
and the airmass will begin moderating. Highs Thursday are
forecast to be in the upper 20s to upper 30s. The warming trend
will continue into Friday as highs will push into the upper 30s
to lower 40s.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
A cold front has moved through the area, and winds have shifted
to the north at all TAF sites. Rain has also come to an end, and
any remaining MVFR ceilings at KCVG/KLUK/KILN will dissipate in
the next hour or two. Through the rest of the TAF period, skies
are expected to remain VFR and mostly clear, mainly with just
some high clouds.
With very light north to northeast winds and clear skies
tonight, some MVFR/IFR fog appears possible at KLUK.
OUTLOOK...MVFR conditions are expected at times from Sunday
night through Tuesday. Gusty winds are possible Monday night
into Tuesday.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...McGinnis
NEAR TERM...Hatzos/McGinnis
SHORT TERM...McGinnis
LONG TERM...Sites
AVIATION...Hatzos
Area Forecast Discussion
National Weather Service Jacksonville FL
849 PM EST Fri Dec 6 2019
.UPDATE...
Mid level shortwave in northwest flow aloft to exit the GA/FL
coastal waters by midnight. Virga associated with this disturbance
will end from west to east across SE GA and adjacent coastal
waters by 03Z per mosaic radar composite and HRRR trends.
Otherwise...an inverted surface trough axis with SCT SHRA to remain
east of the GA/FL coastal zones tonight. A weak low pressure
system will drop into the Western Gulf as well, but not a player
for SE GA/NE FL. Weak high pressure will bridge these two systems
bringing dry conditions to the forecast area. Extensive mid-high
cloudiness expected along and north of I-10 mainly this evening as
the aforementioned shortwave darts through the forecast area.
Less cloud cover anticipated overnight in wake of this feature.
Further south...skies mostly clear per model time/height plots.
Winds shift light northerly tonight. Temperatures will range from
the mid to upper 40s inland to the mid 50s coast.
.MARINE...
No significant changes to the coastal waters forecast for
tonight. Winds will eventually turn to the north tonight
increasing to around 10 kt by sunrise Saturday, with further
increases in wind speeds during the day Saturday.
&&
.PREV DISCUSSION [614 PM EST]...
.Near Term.../through Saturday/...
The region will be between an inverted trough off the Atlantic
coast, and a low approaching from the central Gulf coast Tonight,
with a weak frontal boundary stretched across area between these
systems. An upper trough will move across region this afternoon
and evening. Additional cloud cover will accompany this trough,
with a few sprinkles or light showers possible. During the day
Saturday, the trough to the east will move further east, as low
over gulf moves slowly to the southwest of the region. High
pressure will ridge south across the region, pushing weak frontal
boundary to the south. Mainly dry conditions anticipated for
Saturday, but a brief shower can not be ruled out.
Temperatures will trend near normal this period.
.Short Term.../Saturday night through Tuesday night/...
Atlantic coast trough will move west back toward the coast Saturday
night into Sunday, while the low over the gulf weakens, and ridge
continues over forecast area extending from high to the north. A few
showers will be possible, mainly near the coast.
The low pressure areas weaken Sunday night into Monday, with high
pressure building to the east. The high will sink to the southeast
Monday night into Tuesday morning as a cold front approaches from
the northwest. This front will move through Tuesday afternoon into
Tuesday night, with a round of showers expected to accompany it.
Temperatures will trend above normal this period.
.Long Term.../Wednesday through Friday/...
High pressure will build to the northwest Wednesday, pushing the
front to the south. High pressure will strengthen to the north
Wednesday night into Thursday. This will lead to a period of
enhanced onshore flow, and the potential for mainly coastal showers.
The high will build to the northeast Thursday night into Friday
increasing the onshore flow and potential for showers.
Temperatures this period trend near normal Wednesday into Thursday,
then above normal for Friday.
.AVIATION...
[Through 00Z Sunday]
Extensive mid-high cloudiness expected along and north of I-10
mainly this evening as a shortwave darts through the forecast area.
Less cloud cover anticipated overnight in wake of this feature.
Further south at KGNV and KSGJ...mostly clear conditions. Surface
winds will gradually become light northerly. Broken cumulus field
around 5000 feet should develop after 15Z SAT as winds turn moist
northeasterly at 7-11 knots.
.Marine...
An inverted trough will be over the coastal waters through Sunday
night. High pressure will build to the east southeast Monday into
Tuesday. A cold front will move southeast across area waters late
Tuesday into Tuesday night. High pressure will build to the
northwest Wednesday.
Rip Currents: SE GA Low Risk Saturday
NE FL Moderate Risk Saturday
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 46 67 46 65 52 / 10 10 0 10 10
SSI 52 64 54 65 56 / 10 0 10 10 10
JAX 47 69 54 69 55 / 0 10 20 20 10
SGJ 52 69 57 72 57 / 0 10 30 30 10
GNV 46 70 54 73 56 / 0 10 10 10 10
OCF 46 71 54 76 56 / 0 10 10 20 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&
Area Forecast Discussion
National Weather Service Melbourne FL
1005 PM EST Fri Dec 6 2019
.DISCUSSION...
Temperatures have fallen quickly after sunset under clear skies and
very light to calm winds. Min temps will generally be in the low to
mid 50s, except upper 40s over Okeechobee county and western (rural)
Indian River and St Lucie counties as well NW Volusia/Northern Lake.
With good radiational cooling occurring, full recovery of RH is
expected in many areas, so patchy ground fog should form. But
widespread fog is not expected.
On Saturday, high pressure ridge nosing down the eastern seaboard
will produce a light north to northeast wind flow. Skies will be
mostly sunny in the morning but there will be an increase in mid
level cloudiness (altocumulus) by afternoon esp from Orlando
northward. No rain is expected as low levels will remain pretty dry.
Max temps will range from the lower 70s along the immediate Volusia
coast to the upper 70s over the south interior (Okeechobee and
adjacent western Treasure coast counties).
&&
.AVIATION...
Mainly VFR next 24 hours. Favorable radiational cooling conditions
overnight should lead to some patchy shallow ground fog. However,
significant fog is not expected per LAMP and HRRR guidance. Will
therefore leave any mention out of the TAFs at this time.
&&
.MARINE...
No significant changes to current coastal waters forecast.
Tonight-Saturday...Favorable boating conditions expected, with
veering wind flow from southerly to westerly overnight 5-10 knots,
becoming northerly tomorrow. Seas will range from 1-2 feet tonight,
increasing up to 3 feet well offshore late Saturday.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 51 72 62 74 / 0 10 30 30
MCO 53 75 58 77 / 0 0 10 20
MLB 53 76 63 76 / 0 0 10 20
VRB 53 76 63 77 / 0 0 10 10
LEE 51 74 57 76 / 0 10 20 20
SFB 52 74 58 76 / 0 0 20 20
ORL 54 75 58 77 / 0 0 20 20
FPR 53 77 64 77 / 0 0 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
&&
$$
Kelly/Blottman
Area Forecast Discussion
National Weather Service Shreveport LA
937 PM CST Fri Dec 6 2019
.UPDATE...
Only minor changes during this update. Added additional cloud
cover the the entire region as cirrus continues to move into the
region from the northwest. Also, made slight adjustments to the
diurnal temperature trend overnight to reflect current trends.
Otherwise, the remainder of the forecast remains on track. /20/
&&
.PREV DISCUSSION... /issued 814 PM CST Fri Dec 6 2019/
AVIATION...
VFR conditions across the TAF sites currently. However, patchy
low cigs will develop and move across the region. Additional low cigs
and patchy fog may redevelop overnight, bringing additional
flight category reductions to portions of the region. Otherwise,
expect nwly winds around 10 kts to gradually veer around to the ne
by sunrise Saturday. /20/
&&
PREV DISCUSSION... /issued 405 PM CST Fri Dec 6 2019/
SHORT TERM.../Tonight through Saturday Night/
The latest RAP mid-level analysis indicates a 500mb short wave
now well east of the area in Alabama. In the wake of this feature,
the area is in a northwesterly mid-level flow. At the surface, a
weak area of relatively low pressure (1017 mb) is centered over
southern Louisiana and moving into the northern Gulf of Mexico
with a 1029mb high centered well north of the area in Iowa.
Diurnal cumulus have develop in an area from Texarkana southwest
into east Texas and across central Louisiana with mostly sunny
skies otherwise.
There is HRRR/NAM 3km agreement that the area will remain in a
mid-level northwesterly flow will slowly become more zonal with
conditions staying dry as a surface high passes well north of the
area through Saturday. Diurnal cumulus will mostly diminish this
evening with some pre-dawn stratus developing and patchy fog
possible Saturday morning. Partly to mostly sunny skies will
decrease in coverage through the day on Saturday with mostly clear
skies Saturday night.
For temperatures, lows tonight will range from the upper 30s
northwest of the I-30 corridor to the upper 40s in central
Louisiana and Deep East Texas. Saturday will be a comfortable
late Fall day with highs ranging from the upper 50s in
southwestern Arkansas and McCurtain County, Oklahoma to the mid
60s in Deep East Texas and central Louisiana. Lows on Saturday
night will range from the near 40 in southeastern Oklahoma and
southwestern Arkansas to the mid 40s across much of East Texas and
northern Louisiana. /04-Woodrum/
LONG TERM.../Sunday through Friday Night/
Starting 12z Sunday, generally zonal upper level flow is expected
across the area throughout the day Sunday and into Monday
morning. Southwesterly low level flow will make a return to the
area by early Sunday morning. Meanwhile, a deep upper level trough
will begin digging south across the western CONUS. As this trough
works eastward, an associated cold front will begin to move
through the area by Monday afternoon. Forcing will be sufficient
ahead of the front to support scattered showers to develop. The
best chances for precipitation across the area will come post-
frontal on Monday night and continue through early Tuesday night.
We should see a brief break in the rain for much of the day
Wednesday and into Thursday afternoon before another deep upper-
level trough is expected to move through the late Thursday night
into early Friday morning. There remains some model disagreements
in regards to this trough, anywhere from abundant moisture to no
moisture. As a result, will leave mention of some low end PoPs in
to account for the potential.
Despite increasing cloud cover on Sunday, temperatures will be
around 5 to 10 degrees above seasonable normals. These unseasonably
warm temperatures will continue Sunday night and into Monday. Monday
will be the warmest day of the upcoming week as temperatures climb
to around 10 to 15 degrees above normal. In the wake of the passing
cold front Monday afternoon, temperatures will fall to and remain
below normal throughout the remainder of the week. Tuesday night
will be the coolest night of the week with portions of the area
possibly seeing sub-freezing temperatures.
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 48 63 46 67 / 0 0 0 0
MLU 48 60 46 67 / 0 0 0 0
DEQ 39 59 41 63 / 0 0 0 0
TXK 42 58 43 64 / 0 0 0 0
ELD 42 59 42 64 / 0 0 0 0
TYR 44 62 46 68 / 0 0 0 0
GGG 45 63 45 68 / 0 0 0 0
LFK 50 66 47 69 / 0 0 0 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
20