Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/14/23
Area Forecast Discussion
National Weather Service Corpus Christi TX
541 PM CST Mon Feb 13 2023
...New AVIATION...
.SHORT TERM...
(Tonight through Tuesday night)
Issued at 347 PM CST Mon Feb 13 2023
Key Messages:
- Warming trend continues through Tuesday.
- Winds will continue to strengthen from the south-southeast
through tonight.
- Frequent gusts to Gale Force are expected late tonight through
mid morning Tuesday from 20 to 60 nautical miles offshore. A few
gusts to gale force will be possible across the bays and nearshore
waters tonight.
A deepening upper level low across the Desert SW will lift northeast
across TX tonight, resulting in a strengthening southerly low level
jet. Models vary between a 35 to 45 knot LLJ overnight. Some mixing
will lead to breezy southerly winds across S TX overnight.
The main concern is how much of that jet will mix over the bays and
coastal waters. Since water temperatures are relatively cool in the
upper 50s across the bays and nearshore waters, am not expecting too
much mixing of the LLJ to the surface, but am expecting a few gusts
to gale at times. The offshore waters are a bit warmer with SST near
70 degrees. The LLJ will also be ushering in warmer air temperature.
Several models also show lapse rates across the coastal waters
conducive for mixing. In addition, the HRRR indicated sustained
winds around 30kts with gusts to 35-40kt across offshore waters.
Probabilistic ensembles show a 50th percentile of 30kts or greater
across the offshore water, as well. Given all of these factors, have
issued a Gale Warning for tonight through mid morning Tuesday for
the offshore waters. Small Craft Advisories are in effect for the
bays and nearshore waters with occasional gusts to gale possible.
The upper low will bring a dryline/frontal boundary across S TX
Tuesday which will decrease wind speeds as it moves eastward through
the day. The boundary is progged to reach near the coastline by late
Tuesday morning or early Tuesday afternoon, then it washes out with
a weak to moderate onshore flow returning to S TX by Tuesday night.
There is a slight chance of showers tonight, mainly after midnight,
across northern and eastern portions of S TX. PWATs are progged to
increase to 1.2 inches across the northeast CWA. With the slightly
deeper moisture, the strong LLJ could provide moisture convergence
for a few showers to develop. A few showers continue Tuesday morning
ahead of the dryline, then dry out from west to east. As onshore
flow returns Tuesday night so does a slight chance of showers,
mainly along the coast north of Rockport.
&&
.LONG TERM...
(Wednesday through next Sunday)
Issued at 347 PM CST Mon Feb 13 2023
Key Messages:
- Warm Temperatures in the 80s Wednesday afternoon
- Cold front late Wednesday/Early Thursday
- Elevated fire weather conditions Thursday
- Cold temperatures and windchill below freezing Thursday night
A mid-level trough will sweep across the Great Plains Thursday
followed by weak ridging towards the end of the week and then quasi
zonal flow Sunday. Sunday night a low dives south just off the CA
coast then swings northeastward as it`s cross over the Baja
peninsula with high pressure over the central Gulf resulting in
southwest flow across South Texas. A cold front moves across the
region Wednesday night into Thursday reaching the coast around 12Z.
Strong winds across the inland areas will increase the risk of
Elevated fire weather Thursday and very strong winds over the waters
will lead to Small Craft Advisory conditions with gusts to gale
possible.
Afternoon temperatures ahead of the front on Wednesday will range in
the 80s across the region followed by a 20-25 degree drop in high
temps for Thursday. Overnight lows Thursday and Friday nights will
dip into the mid to upper 30s with windchill in the mid 20s to mid
30s early Friday from the northern Coastal Bend to Victoria
Crossroads and the northern Coastal Plains. Then high temperatures
will warm over the weekend back to the mid 80s by Monday.
Some Patchy sea fog will be possible Wednesday morning this week
as dewpoints rise above SST`s by a few degrees. Isolated showers
east will be accompanied by isolated showers and thunderstorms
over the waters Thursday. The rest of the long term period is
expected to be mainly dry and settled.
&&
.AVIATION...
(00Z TAFS)
Issued at 531 PM CST Mon Feb 13 2023
VFR conditions and gusty winds this evening, but CIGS will
gradually decrease through the night and all sites will likely see
MVFR CIGS for a time late evening and overnight. Winds remain
elevated at most sites with a 40-45kt LLJ above the surface. While
wind shear criteria are not being met due to winds remaining
elevated at the surface, expect a sharp increase in winds above
the surface. A boundary moves through the area on Tuesday shifting
winds to the west and northwest, still with strong gusts. VFR
conditions return behind the boundary tomorrow as low clouds clear
out leaving just some high clouds.
&&
.MARINE...
Issued at 347 PM CST Mon Feb 13 2023
A strong to very strong southerly flow is expected tonight.
Occasional gusts to gale force will be possible across the bays and
near shore waters with more frequent gusts to gale expected over the
offshore waters. A Gale Warning is now in effect for the offshore
waters tonight through Tuesday morning with Small Craft Advisories
in effect for the bays and nearshore waters. The flow will weaken
and shift to the southwest and west by Tuesday afternoon as a front
moves into south Texas. Weak to moderate onshore flow is expected by
Tuesday night. Weak to moderate onshore Wednesday will become
very strong northerly flow after the front moves offshore Thursday
morning. A Small Craft Advisory may be needed Thursday through
the early evening hours on Friday with a few hours of Gale winds
possible. Northeasterly flow becomes moderate late Friday then
weak to moderate as winds shift back to onshore over the weekend.
Patchy sea fog will be possible Wednesday morning followed by
isolated showers and thunderstorms on Thursday.
&&
.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi 64 80 58 81 / 10 10 10 0
Victoria 62 78 53 78 / 30 30 10 10
Laredo 59 83 57 89 / 0 0 0 0
Alice 62 82 53 86 / 10 0 10 10
Rockport 61 75 57 73 / 20 10 10 10
Cotulla 60 82 54 89 / 10 0 0 0
Kingsville 63 82 57 86 / 10 0 10 0
Navy Corpus 64 75 62 73 / 20 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...Small Craft Advisory until 9 AM CST Tuesday for GMZ231-232.
Small Craft Advisory until 9 AM CST Tuesday for GMZ236-237.
Small Craft Advisory until 6 PM CST Tuesday for GMZ250.
Small Craft Advisory until 6 PM CST Tuesday for GMZ255.
Small Craft Advisory until 9 PM CST this evening for GMZ270-275.
Small Craft Advisory from 9 AM to 6 PM CST Tuesday for GMZ270-
275.
Gale Warning from 9 PM this evening to 9 AM CST Tuesday for
GMZ270-275.
&&
$$
SHORT TERM...TE
LONG TERM....BF
AVIATION...PH/83
Area Forecast Discussion
National Weather Service Flagstaff AZ
256 PM MST Mon Feb 13 2023
.SYNOPSIS...Rain and snow showers develop this morning into the
afternoon, especially along the Mogollon Rim. A much stronger
storm system then brings much colder temperatures and strong winds
for Tuesday and Wednesday, with periods of snow for nearly all of
northern and central Arizona.
&&
.DISCUSSION...through Tonight...An upper-level low continues to
move across Arizona this afternoon. Scattered showers have
developed across much of northern Arizona, with an area of banded
precipitation across central Arizona. As the low tracks eastward
through the day, the aforementioned band will continue to trek
northeast along with increasing shower coverage across much of
northern Arizona. Latest RAP guidance shows that the strongest
frontogenetical forcing is expected to remain south and east of
Flagstaff along the Mogollon Rim into the White Mountains. Thus,
the heaviest precipitation this afternoon and evening is expected
to over these areas.
The current forecast has around 2-4 inches forecast above 6500 feet,
with up to 4-8 inches possible in the heaviest snow. Additionally,
with the cold-core of the low overhead, some embedded thunder may be
possible.
As the system moves into New Mexico, precipitation coverage and
intensity begins to wind down, with only a few lingering showers
expected through the overnight.
Tuesday through Wednesday...Behind the first system, a stronger
longwave trough begins to dig into the Great Basin. Moisture
increases over the region, in addition to the remnant moisture from
the previous system, which will allow for precipitation to develop
starting Tuesday morning. Upslope-forced showers along the southward
facing terrain look to be the initial areas to see snow.
Later in the afternoon the main show begins as an intense band of
heavy precipitation is then expected to move across the region from
west to east through the afternoon into the overnight. 12Z HREF
guidance has significant potential (~80% chance) for 1-2 inch/hour
snowfall rates with this band over the higher terrain, especially
from Flagstaff to Happy Jack to Forest Lakes.
Very cold temperatures are expected with this system, which will
allow for snow levels to fall down to around 3500 feet by Wednesday.
Meaning that all but the lowest elevations of southern Yavapai and
southern Gila Counties should expected to receive some accumulating
snow. The greatest accumulations from this system, are expected to
mainly be found above 6000 feet, where 6 to 12 inches are expected,
with up to 18 inches possible in the heaviest snow. Lighter
accumulations of 1 to 3 inches are expected for elevations between
3500 and 6000 feet.
In addition to the snow, strong southwest winds 20-30 mph with gusts
45-55 mph are expected on Tuesday. The gusty winds and heavy snow
will make travel even more difficult, with poor visibility in blowing
and drifting snow. The wind will also make for very cold
temperatures, with wind chills in the single digits over the higher
terrain.
Travel late Tuesday into early Wednesday across the High Country is
STRONGLY DISCOURAGED. Heavy snow and blowing snow will reduce
visibility on area roadways and lead to dangerous driving conditions.
If you must travel, plan on snow covered roads and poor visibility.
Be prepared for the potential to be stuck on area roadways for
several hours.
Wednesday Night through Friday...Dry, and cold northerly flow moves
into the region behind the trough late Wednesday. Clearing skies,
light winds, and a fresh snow pack will help temperatures plummet
overnight into Thursday morning. Widespread single digits to below
zero temperatures are expected across the high country, with much of
the lower elevations dipping into the 20s. Additionally, wind chill
values as low as -15 will be possible in any windier location over
the high terrain Thursday morning.
High pressure begins to build through the day Thursday, allowing
temperatures to rise a bit over the previous day, however we remain
cold.
Saturday through Sunday...Continued dry conditions and gradually
warming temperatures is expected through at least Saturday. Model
guidance continues to hint at the potential for another system, late
in the weekend as the ridge breaks down and a cut-off low forms off
the West Coast. However, uncertainty remains high with this system,
but nevertheless unsettled weather looks to potentially make a
return again next week.
&&
.AVIATION...For the 00Z TAF package...Expect local MVFR conditions
in showers through 06Z along and south A KGCN-Four Corners line,
primarily over the mountains. Winds generally southwest at 15-25
kts. After 06Z, a strong weather system will approach with the
coverage of MVFR/IFR conditions and snow showers gradually
increasing through Tuesday morning becoming widespread by midday
Tuesday. In addition, southwest winds will strengthen, gusting to 45-
55 kts along and downwind of terrain features by early Tuesday
morning. Aviation discussion not updated for TAF amendments.
&&
.FIRE WEATHER...Showers, mainly in the form of snow, becoming likely
on Tuesday then lingering into early Wednesday. Southwest wind gusts
in the 30 to 50 mph range on Tuesday shifting to lighter from the
northwest on Wednesday. Cold both days.
Thursday through Saturday...Look for dry conditions. Locally gusty
northeasterly winds on Thursday and Friday will shift to southerly
on Saturday. Cold on Thursday with a slight warmup on Friday and
Saturday.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning from 6 AM Tuesday to 6 AM MST Wednesday for
AZZ004-006>008-015-038.
Winter Weather Advisory from 6 AM Tuesday to 6 AM MST Wednesday
for AZZ005-012.
Winter Storm Warning from noon Tuesday to 6 AM MST Wednesday for
AZZ009>011-013-014-016>018-039-040.
Winter Weather Advisory until 11 PM MST this evening for
AZZ015>017.
&&
$$
PUBLIC...Humphreys
AVIATION...McCollum
FIRE WEATHER...McCollum
For Northern Arizona weather information visit
weather.gov/flagstaff
Area Forecast Discussion
National Weather Service Jacksonville FL
832 PM EST Mon Feb 13 2023
...New UPDATE...
.UPDATE...
Issued at 825 PM EST Mon Feb 13 2023
Forecast remains on track with a slightly colder night in store.
Just some high thin cirrus clouds tonight and light winds as an
area of high pressure around 1018 mb over the eastern Gulf of
Mexico pushes eastward into the forecast area overnight. Potential
for patchy frost as lows dip to the mid and upper 30s inland and
lower 40s closer to the coast. The HRRR and NAM models suggest
some patchy fog for the Suwannee Valley area which could be more
of an advective fog due to westerly flow off the Gulf of Mexico
Monday afternoon, but model soundings and other guidance do not
support it. In addition, airmass (00z JAX sounding PWAT 0.30
inches) just too dry to mention patches of fog at this time. For
the marine forecast, very little change for the CWF update.
&&
.NEAR TERM...
Issued at 322 PM EST Mon Feb 13 2023
Dry weather, cool temperatures, and clear skies will continue
through the rest of today and overnight as the influence of high
pressure affects the southeastern US. Potential for frost
development over inland southeast Georgia and portions of inland
northeast Georgia. Overnight low temperatures will drop down into
the 30s for inland areas and into the 40s along the coastline.
&&
.SHORT TERM...
(Tuesday through Wednesday) Issued at 322 PM EST Mon Feb 13 2023
High pressure conditions will continue to dominate weather
conditions on Tuesday and Wednesday as high pressure ridging
extends over the forecast area as the center of high pressure
moves off towards the northeast. Prevailing flow will shift about
to become more out of the southwest during this period resulting
in increased moisture levels and cloud cover by Wednesday. High
temperatures going into midweek will reach up into the 70s and
lower 80s by Wednesday. Overnight low temperatures during this
period will warm into the 50s by Wednesday.
&&
.LONG TERM...
(Thursday through Saturday) Issued at 322 PM EST Mon Feb 13 2023
Showers and possible thunderstorms will cross over the forecast
area by the end of the week ahead of an advancing cold front
moving in from out of the west. High pressure conditions will
settle in over the region following the fropa bringing in dry
weather, clearing skies, and breezy winds. Temperatures will be
well above the seasonal average prior to the passage of the cold
front at the end of the week and then drop to below average levels
by the weekend as colder air settles in over the region.
&&
.AVIATION...
(00Z TAFS)
Issued at 648 PM EST Mon Feb 13 2023
VFR with dry air and light flow over the region. Expect VFR to be
persistent overnight over all sites with very light winds - possibly
dropping to calm over some interior sites. Areas or widespread
fog is not expected overnight due to very dry airmass despite
strong radiational cooling. Hi-res models such as HRRR and RAP are
suggesting patchy fog over some interior areas (especially
Suwannee Valley/GNV area) briefly around sunrise. However, given
dry airmass and NAM model soundings, confidence is not high
enough to include in fcst. Very shallow and brief patchy fog
cannot be ruled out late tonight and early Tuesday morning,
however.
Otherwise, some high clouds are expected to build from the west
around mid to late morning Tuesday, but dry low levels are
forecast to persist and therefore VFR. Sfc winds on Tuesday
will initially be light easterly, becoming southeast 5-10 kt by
around 17z-18z.
&&
.MARINE...
Issued at 322 PM EST Mon Feb 13 2023
High pressure will build overhead Tonight. The high will build
more toward the east northeast Tuesday through Thursday. A cold
front will move southeast across the area Thursday night into Friday.
Advisory level conditions are forecast following the cold front. High
pressure will build to the northwest Friday night, then north on
Saturday.
Rip Current Risk: Low risk of rip currents for area beaches today.
Threat increases to moderate on Tuesday as winds shift to onshore.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 37 71 49 78 / 0 0 0 0
SSI 44 66 54 73 / 0 0 0 0
JAX 38 72 52 80 / 0 0 0 0
SGJ 44 70 56 76 / 0 0 0 0
GNV 38 75 51 81 / 0 0 0 0
OCF 39 76 51 81 / 0 0 0 0
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&
$$