Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/09/20

AREA FORECAST DISCUSSION

National Weather Service Albany NY

1036 PM EDT Wed Apr 8 2020

.SYNOPSIS...
Weak high pressure will build in tonight, as clouds will
increase ahead of the next system approaching from the west. A
strong low pressure system and its cold front will bring showers,
windy conditions and a chance of thunderstorms south of the Capital
Region tomorrow. Much colder temperatures and windy conditions will
persist Thursday night into Friday with accumulating mountain
snowfall over the western Adirondacks and southern Greens. High
pressure builds in Friday night into the weekend with fair and cool
temperatures.

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Clouds over the region are exiting and a zone of clearing will
track through tonight. The zone of clearing and light winds will
help temperatures fall to forecasted lows. Convection and
convective debris will spread over the region later tonight and
the leading edge of some rain will arrive just before daybreak
in many areas. Just some minor adjustments to temperatures and
sky cover through tonight. Previous AFD has a few more details
and is below...

The next potent short-wave will be approaching the western-
central Great Lakes Region, and the Midwest tonight. Clouds will
quickly thicken and lower with some isentropic lift ahead of
the warm front to the system bringing some light rain
predominately west of the Hudson River Valley prior to sunrise.
The winds will be light to calm early, but then start to
increase from the south to southeast at 5 to 15 mph shortly
before sunrise. The winds should be strongest funneling up the
Hudson Valley and in the confluent area of the Capital Region.

Lows temps will be challenged by the clouds thinning, but then
increasing. We tried to forecast mins close to the GFS/ECM/NAM
MOS blend and have the lows between 2-5 am. Expect mid and upper
30s over the higher terrain, and upper 30s to lower 40s in the
valley areas.

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
Tomorrow...A fairly dynamic wave and its associated cold front
will impact the region in the late morning into the early
afternoon. A deepening short-wave ahead the left exit region of
a mid and upper level jet streak will impact the forecast area.
Heights will be falling, and mid level lapse rates will be
steepening, as the sfc low deepens to 980-985 hPa lifting
north/northwest of Albany by 18Z. Some digging short-wave
energy will allow for the trough to become negatively tilted.

A couple of bands of showers and some thunderstorms could impact
the region. The latest HREFS, 3-km NAMnest, 3-km ARW-WRF, and
the 3-km HRRR are hinting at some elevated instability being
over the area ahead of the cold front. MUCAPEs are in the
100-300 J/kg range especially closer to KPOU and the I-84
corridor. We are concerned a lack of heating or destabilization
may inhibit deeper convection. The low-level winds are
impressive, but a low-level inversion seen on the model
soundings may inhibit strong or borderline severe winds making
their way to the sfc. We are in decent agreement with SPC with
the Marginal Risk grazing the southern 5 zones. We can not rule
out a rogue isolated severe. Basically locations south of the
Capital Region (We will break away these area in the HWO). We
kept a chance of thunder in these areas, and went with slight
chances over the Capital Region/Mohawk Valley/northern
Catskills. We think these cells may fire along the prefrontal
trough zone or just west of it. There may be a narrow cold
frontal rainband that follows with the burst of strong cold
advection. Some of the CAM`s and HREFS show this. Some of the
wind gusts may flirt with wind advisory values, and bullet SPS
statements may account for gusts 40-45+ mph. PWATs briefly rise
above normal as some localized burst of rain are possible. Rain
rates may briefly be about a quarter inch per hour. Along the
triple point to the system, a secondary wave may form near Long
Island or southeast New England.

The trend will be for a dry slot to bust into the region from
the southwest by the mid to later portion of the afternoon with
brisk and cooler conditions. Expect west winds to increase to 15
to 30 mph with some gusts in the 30-40+ mph range. Max temps
will be in the upper 40s to lower/spotty mid 50s in the valleys,
and 40s to lower 50s over the mtns, but then fall off in the
afternoon in the cold advection. Some of the showers will
transition to snow over the western Adirondacks/southern Greens
/2000-2500 ft range/ before nightfall. The NAM momentum
transfer profiles indicate a few wind gusts may flirt with
advisory levels at Albany prior to sunset. We will continue to
monitor this.

Thu night...A chilly cyclonic flow sets up over NY and New
England, as a broad upper level trough will be over the Great
Lakes Region, southeast Canada, NY and New England. Two low
pressure centers will consolidate and merge near northern ME
with wrap around moisture impacting the forecast area. Some
moisture will be tapped from Lakes Ontario and Erie. We will
likely see westerly upslope snows persists most of the night
over the western Adirondacks/southern Greens with a few inches
(a few localized 3" or so amounts are possible). Rain may mix
with some wet snow in the Capital Region/Mohawk Valley towards
sunrise. A coating to a few tenths may occur on the grassy
surfaces in a few spots (better chance in the western Mohawk
Valley). The winds will remain blustery overnight, and should
crank up more towards day break. Lows will be in the mid 20s to
around 30F over the mountains, and 30-35F in the valley areas.

Fri-Fri night...Additional wet snow accums are possible Fri-Fri
night over the western Adirondacks, and southern Greens.
Another 1-3" may occur especially for the western Adirondacks.
It is unclear if this will be occur over a 12-hr period, but
some long duration tallies could be in a 2-6" before tapering
FRI evening, but this is over several periods. The best would be
northern Herkimer and extreme western Hamilton Counties. The
winds will be blustery at 15-30 mph with some gusts in the 35-45
mph range. We may have to place a wind advisory for some
locations on FRI (if widespread wind gusts of 46-57 mph are
expected), as the 970 hPa cyclone spins over New Brunswick. The
low-level wind fields are decent, but intervals of clouds with
slight or low chances of light rain showers in the valley areas
and the snow showers over the higher terrain /diurnal effects/
could prevent deeper mixing. We will leave this in the HWO for
now. The upslope and lake enhanced snow showers should diminish
Fri night with ridging building in from the south and west.
Below normal temps for FRI with lower to upper 40s in the
valleys, and 30s to lower 40s over the higher terrain. Expect
20s to lower 30s over Fri night with slowly diminishing winds.

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Saturday-Saturday night, lingering cold cyclonic flow may favor lots
of clouds to start Saturday, but rising heights and slow infusion of
drier air from the west should allow for some clearing in the
afternoon, especially in valley areas. Mainly clear and chilly for
Saturday night. Highs Saturday in the 40s to lower 50s, except 30s
across higher terrain areas. Lows Saturday night in the 20s to lower
30s, with some teens possible across portions of the SW Adirondacks.

Sunday-Monday, remnants of upper level low, currently located off
the southern CA coast, tracks across the southern Plains/MS Valley,
and eventually into the Ohio Valley and eastern Great Lakes. Warm
conveyor belt associated with system should move into the region
late Sunday night into Monday, which is when highest probabilities
for rain are indicated. However, some showers may develop ahead of
the main forcing by Sunday afternoon, especially areas west of the
Hudson River, where slight chance to low chance PoPs are indicated.

There are some signals for briefly heavy rain to occur with this
system late Sunday night into Monday morning, especially across the
SE Catskills, mid Hudson Valley into NW CT and possibly the
Berkshires, as a strong low level jet (at least +2-3 SD southerly
component at H925 and H850) and PWAT`s of +1-3 SD cross this region.
Can not rule out a few convective elements as well. In addition,
with the strong low level jet, will have to watch for strong
southeast winds across typically favored areas (within strong
southeast low level flow regimes) of the Berkshires, Taconics and
southern Greens late Sunday night through Monday morning.

Highs Sunday mainly in the 50s for valley areas and 40s to lower 50s
higher terrain, with some potential for even warmer max temps if
thicker clouds/rain arrive later. Lows Sunday night mainly in the
upper 30s to mid 40s. Monday highs could reach into the 60s in
portions of the Hudson Valley and western New England, with mainly
50s elsewhere.

For Monday Night-Wednesday, lingering showers could mix with snow
across higher terrain areas by Tuesday morning in the wake of the
storm system. However, main upper trough will remain to our west,
with slow advancement toward the east Tuesday into Wednesday. Models
exhibit uncertainty as to how this trough advances east, with some
suggesting a gradual approach of the trough with some showers of
rain/snow late Tuesday into Wednesday as it nears. Other models and
some GEFs members suggest the possibility of a more organized storm
system developing ahead of this trough within a strong low level
baroclinic zone remaining nearby. For now, have indicated chance
Pops for rain/snow showers Tuesday into Wednesday, but there is at
least some possibility for a a steadier/heavier period of
precipitation sometime in this time frame, some of which could be
snow as colder air aloft works into the region.

.AVIATION /03Z THURSDAY THROUGH MONDAY/...
Clouds exiting this evening and VFR conditions expected through
about 10Z-12Z, when lower clouds and the leading edge of some
rain moves into our region.

Next system arrives tomorrow morning with a lowering and thickening
of clouds once again. Light rain will begin around 12Z with
ceilings trending down to MVFR. Periods of moderate to heavy
rain are possible from 15Z to 19Z where ceilings and
visibilities could periodically lower to IFR. A rumble of
thunder cannot be ruled out with some of this activity. We only
have enough confidence to add TS in a PROB30 for KPOU at this
time, but it could extend northward to KALB and/or KPSF in later
updates. Strong wind gusts could also occur in any periods of
moderate to heavy rain. Rain will come to an end near or just
after 19z as the cold front sweeps through. Prevailing VFR
conditions return after 19Z.

Winds will remain at less than 10 kT in variable directions
early this evening, then light and variable at less than 6 Kt
tonight. Wind will then pick up from the south to southeast
Thursday morning at around 10 Kt with some gusts past 20 Kt,
especially at KALB/KPSF. After the passage of the cold front,
winds will shift to the west at near 20 Kt with gusts around 30
Kt.

Outlook...

Thursday Night: Moderate Operational Impact. Windy With Gusts To 30 kts. Chance of SHRA...SHSN.
Friday: Moderate Operational Impact. Windy With Gusts To 38 kts. Chance of SHRA.
Friday Night: Low Operational Impact. Breezy. Slight Chance of SHRA.
Saturday: Low Operational Impact. Breezy. NO SIG WX.
Saturday Night: No Operational Impact. NO SIG WX.
Sunday: Moderate Operational Impact. Breezy. Chance of SHRA.
Sunday Night: High Operational Impact. Breezy. Definite RA.
Monday: High Operational Impact. Breezy. Definite RA.

.FIRE WEATHER...
Weak high pressure will build in tonight, as clouds will
increase ahead of the next system approaching from the west. A
strong low pressure system and its cold front will bring showers,
windy conditions and a chance of thunderstorms south of the Capital
Region tomorrow. Much colder temperatures and windy conditions will
persist Thursday night into Friday with accumulating mountain
snowfall over the western Adirondacks and southern Greens.

The RH values will increase to 85 to 100 percent Thursday
morning, and will lower to 45 to 65 percent in the wake of the
strong cold front. The RH values will be in the 65 to 90 percent
range Friday morning.

The winds will be light and variable direction at 5 mph or less
early tonight and then will increase from the south to southeast
at 5 to 15 mph Thursday morning. The winds will shift to west to
southwest at 15 to 25 mph in the wake of the front with some
gusts in the 35 to 45 mph range. Gusty west winds will continue
Thursday night into Friday.

A widespread soaking rain will occur with the frontal passage
and surface low late Thursday morning into the afternoon. A few
thunderstorms are possible south of Albany.

.HYDROLOGY...
No widespread hydro problems are expected the next several days
and at least through the weekend.

High pressure will briefly build in through most of the night
time period with dry weather. However, a strong front will
bring more rain to the region on Thu. A quarter to a half inch
of rain is expected Thursday with locally higher amounts. While
this rainfall may cause some minor rises on rivers and streams,
no widespread flooding is anticipated.

Cloudy, blustery and cool weather, with more valley rain
showers and mountain snow showers are expected for Thursday
night through Friday night. Some light to isolated moderate
amounts of snow are possible for the western Adirondacks and
southern Green Mtns.

Although most of the weekend will be dry, more rain looks to
return for Sunday night through Monday. Another widespread
soaking rainfall will be possible.

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...None.
MA...None.
VT...None.

$$
SYNOPSIS...Wasula
NEAR TERM...NAS/Wasula
SHORT TERM...Wasula
LONG TERM...KL
AVIATION...NAS
FIRE WEATHER...Wasula
HYDROLOGY...Frugis/Wasula

Area Forecast Discussion

National Weather Service Birmingham AL

1007 PM CDT Wed Apr 8 2020

.UPDATE...
Evening Update.

.SHORT TERM...
/Updated at 0947 PM CDT Wed Apr 08 2020/

Quite a volatile atmosphere across Central Alabama. In fact, the
airmass covers a large section of the central Conus. Severe
thunderstorms that moved over the southern third of the area have
since dissipated after producing large hail and damaging winds.
The atmosphere in the south has been mixed up and this is where
the most stable air resides at this time.

Low level isentropic lift is already working the air in Central
Alabama. The latest satellite imagery has low clouds and fog
developing. Will mention some patchy fog, some of which could be
dense at times. This will only occur ahead of the developing
thunderstorms and will also provide a near surface stable zone.

Concerning the severe potential overnight, we will continue
advertising damaging winds, hail up to ping pong ball size and
the outside shot at a tornado. This activity will be associated
with an approaching cold front from the northwest. Timing remains
about the same after 1-2 am and lasting until just after sunrise.
MUCAPE values may be as high as 2500 with bulk shear of 50kts or
so. There will be plenty of CAPE in the hail growth zone and 500
temps go down overnight. The mean relative humidity values do drop
as the forcing approaches the I-20 corridor and therefore that
seems like a reasonable break point for slight and marginal due
to coverage. Additionally, the large scale forcing does skirt the
northern areas and exits northeast by daybreak.

Previous short-term discussion:
/Updated at 1002 AM CDT Wed Apr 08 2020/

Through this evening:

Current satellite imagery & RAP mesoanalysis indicate a broad fetch
of lingering low-level stratocumulus amidst southwesterly low-level
warm/moist advection. Some patches of clearing can already be picked
out, with storms already ongoing near the ArkLaMiss. Dewpoints in
the mid 60s (mainly northeast) to low 70s suggest MLCAPE of 1,000-
1,500 J/kg as of ~10 AM , with diurnal heating into the upper 70s
lower 80s increasing this to ~2,000-3,000 SBCAPE per our modified
12z RAOB. Focus for convective initiation is subtle, though with WAA
and a diffuse theta-e boundary draped from northwest to southeast,
thunderstorms that get going in the early afternoon could quickly
strengthen to severe limits as eff. bulk shear runs ~50 kts via the
H5 speed max aloft, and relatively unidirectional hodographs support
robust/splitting updrafts. 500 mb temperatures range from -10 to -12
C, suggesting decently cooler air aloft despite effects from deep-
layer ridging southward, as well as drier air near that layer. (This
would favor wet-bulbing and potentially enhance buoyancy in the hail
growth zone.) All things considered, 1-2" hail is possible in
stronger storm cores this afternoon with expectation the most
favorable zone for convective activity will stretch from northwest
to southeast across the center of Central Alabama, generally along
near the lingering/subtle surface boundary dividing the upper
60/lower 70 dewpoints. Damaging winds are also possible as stronger
convective downdrafts tap into 800-1,000 J/kg DCAPE and likely
cluster/cold pool with southeast progression later in the
afternoon/evening. Severe weather timing still remains advertised
from 1 PM to 9 PM with large hail and damaging winds the primary
threats.

40/Sizemore

.LONG TERM...
/Updated at 417 AM CDT Wed Apr 08 2020/

Friday and Saturday:

Cooler and drier air builds in as ridging slides across the Gulf
States on Friday. Upstream, the cut-off low pressure system that has
been hanging back over the Desert SW for several days gets picked up
by the main upper level trough and slides eastward through the Great
Plains. Rain chances could increase Saturday afternoon into the
evening as a pre-frontal shortwave lifts out of the Western Gulf.

Sunday:

The trough is expected to swing through the region on Sunday, and
will likely be the main story weather-wise for the next several
days. A surface low develops and lifts northeastward into the Mid-MS
Valley. This will be a highly dynamic system with strong low level
and upper level jets, increasing the 0-6km shear to upwards of
70+kts. There will be plenty of forcing as the trough and low
pressure system move through, so expect widespread showers and
thunderstorms to develop. The biggest question right now is
instability and timing. The Euro shows the warm front lifting well
to our north, placing Central AL in the warm sector of the
developing low. It also has a slower timing overall, which allows
for more destabilization. However, the GFS is quicker and doesn`t
lift the warm front as far north, which could limit how much
instability we have. The GFS also continues to develop some
convection along the coast, which could limit our instability as
well. Overall, given the strong dynamics of this system and the
thermodynamics currently shown in the model guidance, I`ll add
mention for a slight risk of severe weather for Sunday with
damaging winds, hail, and tornadoes possible. Exact timing remains
uncertain as model guidance continues to flip back and forth.
This has the potential to be a strong system, so it will need to
be monitored closely.

Monday and Tuesday:

The trough is expected to move east of our area by Monday morning,
and drier air builds in. Guidance hints at a secondary cold front
moving through the region Monday night into Tuesday, but there
shouldn`t be any precip along the boundary due to the lack of
moisture return.

25/Owen

.AVIATION...
00Z TAF Discussion.

A cluster of showers and thunderstorms will continue along and
south of I-85 thru 02z, otherwise VFR conds will prevail thru 06z.
A strong cold front will push thru Central Alabama between 08z and
15z. A line of strong to severe storms will accompany the cold
front. The storms will not last for more than a few hours due to
the quick movement of the cold front. Warm and moist southwest
flow will bring widespread MVFR cigs to the area between 06z and
09z. The cigs will rise quickly several hours after fropa, with
VFR conds at sites by 16z. North winds 10-15 kts will prevail
after 15z with gusts to 18 kts.

58/rose

.FIRE WEATHER...

A cold front will sweep through Central Alabama late tonight and
Thursday morning. A line of strong to severe storms will accompany
the frontal passage. The rain will not last for more than a few
hours due to the quick movement of the front. Cooler and drier
conditions will prevail Thursday and Friday. Rain chances return
for the weekend as another system approaches.

.PRELIMINARY POINT TEMPS/POPS...
Gadsden 60 71 46 63 38 / 60 10 10 0 0
Anniston 64 73 48 63 39 / 60 20 10 0 0
Birmingham 65 74 50 64 42 / 60 10 10 0 0
Tuscaloosa 65 76 51 67 43 / 50 10 10 0 0
Calera 64 75 50 66 42 / 60 30 10 0 0
Auburn 63 77 52 66 42 / 30 30 10 10 0
Montgomery 68 80 54 70 44 / 20 30 20 10 0
Troy 68 81 55 70 45 / 10 30 20 10 0

.BMX WATCHES/WARNINGS/ADVISORIES/...
None.

Area Forecast Discussion

National Weather Service State College PA

955 PM EDT Wed Apr 8 2020

.SYNOPSIS...
Expect a short break from the mild spring pattern with
noticeably colder conditions and gusty winds Thursday and
Friday. A strong cold front will deliver much colder air
on Thursday. It will be cold enought for scattered snow showers
over the Allegheny Mountains Thursday night through Friday.
Conditions will improve over Easter weekend with subsiding winds
and moderating temperatures. Next week will start off wet.

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A quiet evening with mostly clear skies throughout central PA.
Clouds increase later tonight ahead of approaching secondary
cold front. Showers associated with this front will reach my
western zones before daybreak. Mins will range from the mid 30s
north to the mid to upper 40s southeast.

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY/...
A strong cold front will sweep across the area tomorrow
accompanied by gusty rain showers. A narrow ribbon of weak
instability along/ahead of the front along with strong winds
aloft will support marginal tstm wind threat primarily east of
the I-81 corridor during the late morning to mid afternoon.

Strong post-frontal winds are expected to drive much colder air
into the region through late week. 35-45 mph gusts will impact
the Lower Susq and a Wind Advisory has been issued from mid
morning through the afternoon hours. Gusty winds will continue
Friday as well accompanied by below normal temperatures,
bringing a chilly bite to the air. Temp curve should be limited
to non- diurnal tomorrow as strong CAA kicks in. Friday will be
the coldest day with highs 10 to 20 degrees below average (mid
30s NW to upper 40 SE). Persistent and relatively cold cyclonic
flow will change rain to snow showers over the Alleghenies with
a few inches of accumulation likely over NW PA and favored
upslope areas Thu night - Friday. Snow showers taper off Friday
evening with gradually improving conditions into Easter weekend.

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
The extended period begins cold as Canadian high pressures
builds into the region Friday night, maintaining breezy
conditions overnight that should prevent widespread frost from
forming over the Lower Susq.

High pressure crosses the area on Saturday with moderating
temperatures (still below avg highs) and dry conditions.
Temperatures continue trend warmer on Sunday with increasing
clouds as high pressure slides off the East coast.

Widespread rainfall expected to begin early next week with
anomalous moisture flux spreading into central PA in advance of
low pressure tracking northeast from the lower MS Valley. Showers
remain possible on Tuesday with secondary cold front crossing
the Appalachians, followed by another shot of colder air for
midweek.

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
As of 00z Thu, skies have cleared out at all airfields. Will
maintain VFR conditions through at least 06z. HRRR model tracks
remnant rain showers from MCS currently over IL into
southwestern airfields by 08z and through the southeastern
airfields by 12z. Confidence is low in whether this rain will
hold together as it moves across the area late tonight.

More well defined forcing for a narrow band of rain showers
moves into northwestern airfields by 11z in the form of a strong
cold front, with showers pushing through to the southeastern
airfields by 16z Thurs. Ahead of this cold front, models
indicate pockets of 35-40 kt LLWS from 09z to 15z as 50 kt
southerly LLJ moves overhead.

Behind the cold front, sfc winds shift to 250-280 degrees and
low level mixing will allow for wind gusts of 30-40 mph Thurs
afternoon. Scattered rain showers in post frontal airmass may
mix with snow and graupel in central and northern airfields
Thurs night.

.Outlook...

Fri...Low cigs/rain/snow showers likely NW 1/2. Gusty winds
25-35kt from 270-300 degrees subsiding Friday night.

Sat...Low cigs psbl early then trending VFR. Light rain showers
psbl late.

Sun...VFR early. Chance rain showers by aftn. Strong/gusty
southerly winds psbl Sunday afternoon depending on
track/development of sfc low forecast to move east from the
Mississippi Valley.

Mon...Reduced cigs/vsbys in widespread rain. Strong/gusty
southerly winds continue turning westerly late in the period.

.CTP WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from 10 AM to 6 PM EDT Thursday for PAZ036-
056>059-063>066.

$$
SYNOPSIS...Gartner/Steinbugl
NEAR TERM...DeVoir/Gartner
SHORT TERM...DeVoir/Gartner
LONG TERM...Jurewicz/RXR/Colbert
AVIATION...Colbert

AREA FORECAST DISCUSSION

National Weather Service Eureka CA

332 PM PDT Wed Apr 8 2020

.SYNOPSIS...Dry weather is expected to persist for most of our
region into next week. Above normal temperatures are expected in
the interior, though somewhat cooler high temperatures will filter
in toward Friday. Marine layer cloudiness will gradually expand
along the coast through the end of the week, keeping conditions
there seasonably cooler.

.DISCUSSION...Marine layer cloudiness dissipated fairly early this
morning, with mostly sunny conditions for the vast majority of
northwest California this afternoon. The lower atmosphere has become
unstable enough over the mountainous terrain of southern portions
of our area to allow for some decent cumulus growth there, aided by
some mid-level moisture. However, there is a strong enough capping
inversion to limit any shower development. Low pressure spinning
over southern California is resulting in plentiful shower and some
thunderstorms there, and will try to send a spoke of deeper
moisture toward Lake County late tonight, but aside from a
thickening of the clouds already passing by there, do not expect
showers to make it that far north. That area of low pressure will
continue to drift southeastward across the southwestern United
States over the next couple of days, with generally drier and more
stable air moving in. Another upper-level trough dropping in from
the northwest will clip our area over the weekend, and with that
there is a non-zero chance of isolated shower development over the
interior mountainous terrain, but am skeptical there will be
enough moisture, so we have not included it in the forecast at
this time. To summarize, expect dry weather across our forecast
area through at least the middle of next week.

With that cleared up, our focus will be on coastal stratus and
temperatures. An inverted surface trough will shift off the
Mendocino coast tonight, allowing southerly winds to send marine
stratus northward toward Cape Mendocino. Some stratus or fog may
try to creep into the lower Eel River Valley tonight, but overall
thinking it will turn out clearer than last night to the north of
the cape. While coastal areas south of the cape may stay cloudy
through much of the day on Thursday, stratus may start to creep
around to Humboldt Bay on northward by the afternoon hours. Where
stratus does not reach during the afternoon, it will be another
mild day, especially farther inland. That said, high temps will
start to take a step back through Friday as the marine layer
deepens. At least overnight and morning low clouds will linger
along the coast into the weekend. Northwest breezes will be found
during the afternoon hours where clearing occurs.

Temperatures will remain near or above seasonal averages through
much of next week, with overall a fairly quiet and benign weather
pattern persisting as strong upper-level high pressure remains
anchored over the eastern Pacific. /AAD

.AVIATION...Low clouds and some light fog across portions of the
coastal plain and interior valleys have dissipated nicely today
courtesy of warmer temperatures and a shrinking marine layer. Expect
low clouds to expand along portions of the coast again this evening
and overnight, but they are expected to be less expansive than last
night. However, a southerly surge of moisture is expected to
commence along the coast S of Cape Mendocino by Thursday morning,
expanding coastal cloudiness northward. High resolution HRRR
guidance shows this surge continuing N around the cape by early
afternoon with the potential for low ceilings by late in the
forecast period.

Mostly VFR conditions are expected to continue at KUKI through the
period. Earlier model guidance suggested low-level winds would
increase after midnight at KUKI with marginal potential for low-
level wind shear, but this may be a bit overdone. /SEC

.MARINE...High pressure over the NE Pacific continues to promote a
strong northerly wind regime over the northern CA coastal waters
through the end of the week and beyond. Short period seas will
continue to build today in response to the prolonged northerlies,
with the worst conditions remaining over the outer waters. Increased
offshore flow on Thursday may induce a brief weakening trend in the
winds south of Cape Mendocino, but the steep short period seas will
likely be enough to sustain the Small Craft Advisory through that
time for the southern outer zone. Meanwhile, stronger winds and
higher seas in the nearshore zones will generally be confined to the
typically favored locations near and downwind of Point Saint George
and Cape Mendocino over the next few days. The nearshore waters
along the Mendocino Coast will remain a little more sheltered from
the northerly wind-driven waves, and thus no advisory is anticipated
for the southern nearshore zone at this time. /CB&SEC

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...None.
NORTHWEST CALIFORNIA COASTAL WATERS...Small Craft Advisory until
noon PDT Thursday for PZZ450-475.

Small Craft Advisory until noon PDT Friday for PZZ470.

Visit us at https://www.weather.gov/eureka

For forecast zone information
see the forecast zone map online:
https://www.weather.gov/images/eka/zonemap.png

Area Forecast Discussion

National Weather Service Austin/San Antonio TX

925 PM CDT Wed Apr 8 2020

.UPDATE...

Despite ample shear and a strongly unstable atmosphere, the lack of
any sustained lifting mechanism prevented severe storm development
this afternoon and evening. A few pulsey cells developed and
dissipated, with radar imagery generally clear at this time save a
few bat colonies and a weak shower in Dimmit County. HRRR continues
to indicate that an isolated shower/storm may impact far southwestern
portions of the area overnight, however generally most locations will
remain dry until more widespread showers and storms are able to
develop Thursday afternoon ahead of a cold front and upper level
disturbance. Those storms will have the potential to become severe
with large hail the primary threat followed by gusty winds and
locally heavy rainfall.

.PREV DISCUSSION... /ISSUED 628 PM CDT Wed Apr 8 2020/

AVIATION...

VFR conditions are expected overnight at all sites. Chances for
thunderstorm development near the terminals this evening appears very
low and so VCTS mentions have been removed. Around sunrise, some
light fog will probably develop at AUS and SSF, and potentially at
SAT, but won`t stick around long and MVFR visibility should be
predominate. VFR conditions should return much of the daytime. As a
cold front and upper level disturbance approach on Thursday
afternoon, shower and storm activity is expected for the I-35 sites.
There is much higher certainty in convective development occurring
tomorrow than there was today. Although the best environment for
strong storms should remain southeast of the terminals, the potential
is there for a few large hail or gusty wind reports. VCTS is
included in the TAF at this time, but will likely be upgraded to TSRA
as confidence increases in subsequent forecasts. For the 30 hour
sites, some of this activity may linger past 00Z on the 10th, but
confidence is lower so have opted for VCSH for that period at this
time.

PREV DISCUSSION... /ISSUED 337 PM CDT Wed Apr 8 2020/

SHORT TERM (Tonight through Thursday Night)...
While fairly quiet at the moment, there is some initial development
of convection along the I-35 corridor as this is being typed. With a
moist and unstable airmass in place in place, a eastward mixing
dryline moving across the area aide in convection. High CAPE values
of 3000-4000 J/kg are present with, now, little to no inhibition as
destabilization is occurring with daytime heating. With continued
development along the I-35 corridor, the potential for convection to
become severe is justified. Day one of the Storm Prediction
Convective Outlook has most of the area under a slight risk with
large hail, potentially being greater than 2 inches in diameter,
being the main threat with strong wind gusts. As convection continues
into the afternoon and early evening, activity should move eastward
and weaken after sunset.

Tonight, convection decrease and becomes a non-threat. Temperatures
and dewpoints remain relatively high, giving us another warm and
muggy night with low temperatures in the low 70s. Early morning
cloud return with possibly some areas of light fog.

Tomorrow, with the moist and unstable airmass still in place, a cold
front is progged to be draped across the Edwards Plateau. The
dropping cold front will be aided by a short wave moving across
South Central Texas. The front will provide better lift than what is
being observed today, and coverage and intensity of convection could
be greater and more widespread. An area of Slight risk covers the
Hill Country and I-35, and a higher risk of Enhanced has been added
to the area between Interstates 10 and 37, by the Storm Prediction
Center with an initial threat of large to very large hail, then
transitioning to a damaging wind threat should the activity become
more linear. Meso models are currently showing initiation over the
Hill Country and Edwards Plateau around 3 to 4 pm local, and moving
into the I-35 corridor between 4 and 6 pm. Locally heavy rainfall is
also a concern for these storm and areas could see up to 2 inches in
a relatively short period. The Weather Prediction Center has the
area highlighted enhanced for excessive rainfall for tomorrow. This
means that there is a 5 to 10 percent chance that the rainfall
exceeds the flash flood guidance and may be subject to flash
flooding. Turn Around Don`t Drown.

Tomorrow night, convective activity moves east and the severe threat
diminishes with only some residual light showers. Low temperatures
will be in the low 60s overnight.

LONG TERM (Friday through Wednesday)...
The first part of Friday should have most of the atmosphere worked
over through either the post-frontal winds or the storms themselves.
Thus Friday morning may begin uneventful. The Rio Grande Plains may
still be able to see a rumble or two, as the frontal layer should be
more shallow there. However, overrunning embedded shortwaves should
enhance rain and storm potential as the day goes on and eventually
expanding east across the whole area by early evening. QPF amounts
are probably going to be lightest during this stormy period, but
there should be enough instability out west for a few marginal
hailstorms. Later in the night, surface winds begin to increase out
of the east and southeast as the parent upper low gets closer to the
Southern Plains. At this point the threat for locally heavy rainfall
(generally 1-2 inches) may become cumulatively the more impactful
time that runoff could cause flooding. Similar to the WPC day 2
outlook the area of runoff concern should be mainly eastern Hill
Country, I-35, and the Coastal Prairies. Dynamics/shear will
probably be stronger with this round of activity, but with a reduced
amount of CAPE, so the magnitude of the severe potential may also
match that of Thursdays event. By Sunday morning even the slower
ECM/Canadian solutions pull the deeper convection west to east for
all rains ending, by no later than midday. The rest of the forecast
is for a cool and dry period late Sunday through next Wednesday as
broad polar troughing over the Central US reinforces the front in the
wake of the southern stream upper low.

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 70 84 60 73 62 / 20 60 30 30 50
Austin Bergstrom Intl Airport 68 83 60 74 61 / 20 60 30 30 50
New Braunfels Muni Airport 71 85 60 73 62 / 20 70 30 40 50
Burnet Muni Airport 66 80 57 72 60 / 20 60 20 30 50
Del Rio Intl Airport 71 87 63 79 64 / - 20 20 40 60
Georgetown Muni Airport 66 81 57 73 61 / 20 60 30 30 50
Hondo Muni Airport 70 87 61 76 63 / 0 40 30 40 70
San Marcos Muni Airport 70 83 60 73 61 / 20 60 30 40 50
La Grange - Fayette Regional 70 86 62 74 63 / 20 70 50 30 30
San Antonio Intl Airport 72 89 61 73 63 / 0 70 30 40 60
Stinson Muni Airport 71 90 62 74 64 / 0 70 30 40 60

.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&

Short-Term/Aviation...KCW
Long-Term...Platt

Area Forecast Discussion

National Weather Service Little Rock AR

752 PM CDT Wed Apr 8 2020

.AVIATION...09/00Z TAF CYCLE

Cannot rule out a few storms forming later tngt acrs parts of
cntrl/srn AR as a CDFNT drops SWD thru the FA. Opted to go with a
mention of VCSH/TS as overall coverage expected to be limited.
Otherwise, VFR conds wl prevail. Sfc winds wl shift to the N/NW
behind FROPA later tngt and linger into Thu. /44/
&&

.PREV DISCUSSION...(ISSUED 248 PM CDT Wed Apr 8 2020)
Short Term...Tonight thru Friday...
We are facing a high CAPE / weak shear type of thunderstorm
environment this evening. Strong H5 low is off the southern CA
coast, and has been ejecting some weak shortwaves to the east.
Subtropical jet is streaming across Baja Ca, over TX, and across AR,
while the polar jet is digging south out of Canada, dropping a trof
over the Great Lakes region. Both jets are essentially converging on
the midsection of the country, creating a somewhat unfavorable upper
level environment for thunderstorm development.

At the surface, a cold front is diving southward across the Plains,
and will be pushing into Arkansas tonight.

The front will be pushing it`s way into a very warm, humid and
unstable airmass. Model soundings have been indicating maximum
MLCAPE values between 2500-5000 j/kg across the eastern half of the
state this afternoon into this evening. While some of this may a bit
overdone, an 18Z sounding here at LZK has indicated a MLCAPE value
of 3300 j/kg, so values upward of 4000 j/kg to the east do not seem
unrealistic. There is not an excessive amount of CIN to overcome, so
with the front pushing into the area, there would appear to be
little to hold back thunderstorm development.

The limiting factor, of course, will be the weakly sheared
environment, in addition to the lack of upper level support - which
may even contribute negatively to the environment.

Midlevel lapse rates are very steep, and if any large storms are
able to develop, there will be a risk for substantially large hail.
My confidence in this scenario is only moderate at the moment, but
the potential for large hail - larger than 2" probably - is
certainly there.

If a QLCS does develop, the inflow environment will also support the
development of shorter-lived tornadoes along the line. It`s possible
this may not happen in the LZK CWA, but again, the potential is
certainly there.

The NAM Nest and WRF NMM models have been more forthright in
developing a QLCS after 00Z and bringing it down into the eastern
half of the CWA, with the line moving down into SE Arkansas well
after 06Z. The HRRR has been much more conservative, generally
keeping most of the activity well to the east. However, the ESRL
HRRR and more recent runs of the HRRR are trending more toward the
NAM/WRF solution. They are certainly not in agreement, but this does
add confidence to the forecast of strong thunderstorms tonight.

Putting it all together, we are probably not looking at a high-
impact widespread severe weather event. Most of the event will
probably occur east of the LZK forecast area. However, there could
certainly be areas of wind damage, large hail, and even a few
tornadoes depending upon what sets up across the area tonight. The
most likely scenario brings a QLCS thru the eastern CWA, which may
not even be a continuous line. We also have to watch for any cells
that develop ahead of the line, especially in this high-CAPE
environment.

With all that said, the cold front should sweep thru the area
tonight and bring dry weather to the area for the remainder of the
short term.

Extended Term...Friday Night thru Wednesday...
The extended period will remain unsettled through the extended
period. Rain chances will begin to increase across the area on
Saturday as an upper level low across the Four Corner`s Region and
attendant cold front move eastward. Chances for rain will linger
through the weekend and into early portions of next week as the low
strengthens over the Natural State. Thunderstorms will be possible,
some of which could become severe, especially across the southern
portions of the state where the instability is more favorable for
convection.

Slight rain chances will linger through early portions of next week
as mean troughing overcomes much of the CONUS, and small
perturbations in the flow intermittently swing through the state.
Temperatures will be much cooler through the extended, especially
after the aforementioned cold front moves through on Sunday.
&&

.LZK Watches/Warnings/Advisories...NONE.
&&

Area Forecast Discussion

National Weather Service Newport/Morehead City NC

1000 PM EDT Wed Apr 8 2020

.SYNOPSIS...
A series of weak disturbances will move across the area into
Thursday with a mainly dry cold front pushing through the area
late Thursday. Cooler high pressure fills in late in the week
before a stronger frontal system impacts the region Sunday into
early next week.

.NEAR TERM /Overnight/...
As of 10 PM Wed...Line of bkn tsra continues to push sewrd
through the FA. The convection has become sub severe, and only
expecting some gusty winds and brief heavy rains, albeit still
observing frequent lightning. Still have pops decreasing
markedly after around midnight when storms should be moving
offshore.

Prev discussion... As of 630 PM Wed...We are watching several
clusters of strong to severe thunderstorms in the nrn NC
Piedmont, which are quickly charging sewrd towards the NC
Coastal Plain, and will arrive in the next couple hours. If they
hold together, they will present and damaging wind and large
hail threat. Chc pops for thunder still in good shape through
midnight.

Prev discussion...As of 345 PM Wed...Upper level analysis shows
deep northwesterly flow aloft with a weak mid- level shortwave
diving out of the Ohio Valley. At the surface, weak and broad
high pressure was situated over the Bahamas with a cold front
stalled near northern Virginia.

Earlier noted outflow boundary has thrown a wrench in the
original forecast with dew points dropping into the low 50s
inland, with resulting RAP analyzed CAPES struggling to reach
500 J/kg along southern portions of the CWA with even lower
values north of Highway 264. This is despite nice warming into
the low to mid 80s. 12Z CAM suite continues to advertise a band
of showers and storms beginning to impact the region from north
to south starting at 23Z, with the latest runs of the HRRR
advertising that line being initiated by outflow from the
current cluster of storms over the Central Appalachians. The
near-storm environment will be characterized with CAPEs of
500-1000 J/kg and effective shear of 30-35 kt, coupled with
straight hodographs, suggesting an isolated damaging wind threat
or hail threat is possible. SPC has our northwest counties in a
Slight Risk with a Marginal Risk elsewhere.

Convective activity is expected to clear the Crystal Coast by
around midnight with partly cloudy skies and light winds in its
wake, although with mild airmass still in place lows will only
fall into the low to mid 60s. Low dewpoint depressions suggest a
patchy fog threat although confidence is low.

.SHORT TERM /THURSDAY/...
As of 400 PM Wednesday...CAMS depict another band of showers
and thunderstorms crossing our area from west to east as part of
a decaying MCS cross the Ohio and Tennessee valleys overnight.
Weak pre-frontal convergence is expected with light
south/southwesterly surface flow. CAMs suggest a ribbon of ~1000
J/kg are possible right around daybreak with dew points in the
low 60s. This, along with effective shear again around 30-35 kt,
points to an isolated strong storm with damaging winds and some
hail. Band will quickly clear the area midday with strong
west/northwesterly winds developing in its wake with sustained
15-20 kts for the coastal plain and gusts up to 30 kts with deep
mixing. Model guidance points to dew points falling into the
upper 40s for the coastal plain although in cases of robust
mixing this can be generous. Given this, there is concern with
increased fire risk tomorrow afternoon with RHs around 30% and
temperatures still climbing into the 80s in downsloping flow. No
headlines necessary yet but next shifts will need to analyze
further.

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
As of 330 AM Wed...A few showers and thunderstorms are possible
Thursday ahead of a cold front that will cross the area later
in the day. Drier and cooler conditions are then on tap for
Friday into Saturday. The next storm system will impact the area
Sunday into Monday with high pressure returning thereafter.

Thursday night through Saturday...High pressure building into
the area behind the front will keep dry conditions in place
Friday and Saturday, with temps below normal both days.
Efficient radiational cooling is expected Friday night, with
lows dipping into the 30s, and the potential for frost away from
the beaches Saturday morning.

Sunday through Monday...Longer range guidance continues to
converge on the solution of a potent H5 shortwave lifting from
the south central US across the Midwest Sunday, with the
associated complex surface low crossing the Tennessee Valley and
riding up the Appalachian Mountains through Monday. This will
likely result in a warm front crossing the area Sunday, with
strong WAA on the back of a 50+ kt LLJ Sunday night into
Monday. Given this wind profile and the potential for
instability to quickly build, severe weather is a concern Sunday
into Monday, as are strong gradient winds, especially along the
coast. Details of the severe threat will be refined in the
coming days, but currently carrying the threat for thunderstorms
Sunday through Monday in the official forecast.

Current expectation is that a cold front will move through
Monday, with generally dry conditions behind it for Tuesday.
However, upper level heights could continue to fall, and dry
conditions are not a guarantee Monday night into Tuesday as
broad lift could occur across the region. Regardless, much
cooler temps are expected Tuesday through the middle of next
week.

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Short Term /through 18Z Thursday/...
As of 630 PM Wed...Mainly clear skies prevail across the
terminals today with only some light cirrus to speak of. Convection
firing across the NC Piedmont will quickly move sewrd towards
the Coastal Plain counties of NC, and may produce strong winds
and breif reductions in vsby this evening, then move well away
by midnight. Coverage is still uncertain enough to preclude
explicit TEMPO groups this cycle, but will be amending if threat
becomes more imminent. Will continuously carry and VCTS.

Another round of showers and storms is possible ahead of an
advancing cold front early tomorrow morning before sweeping
offshore before midday. Strong and gusty westerly winds expected
with this passage with gusts of 25-30 kt possible especially for
coastal plain.

Long Term /Thursday night through Sunday/...
As of 330 AM Wed...VFR prevails through Saturday. A prolonged
period of flight restrictions and LLWS is possible beginning
Sunday as a strong frontal system impacts the area.

.MARINE...
Short Term /Tonight and Thursday/...
As of 415 PM Wed...Southwest to westerly winds prevail over the
waters at 10-15 kts with a few gusts to 20 kt with seas 3-5
feet, except 2 feet to the north. Winds are weaker than expected
with the passing outflow boundary earlier this morning, and
therefore dropped the existing SCA. Cold front will approach and
cross the waters tomorrow around midday with southwest winds
15-20 kt in the morning veering northwesterly at 15-20 kt in
the evening, with seas in the outer southern and central waters
reaching 6 feet by sunset.

Long Term /Thursday night through Sunday/...
As of 330 AM Wed...Winds shift abruptly to breezy NW behind the
cold front, then gradually wane into Friday as cooler high
pressure builds in. A strong frontal system will impact the area
beginning Sunday, bringing the potential stronger winds.

Seas subside gradually Thursday night into Saturday as the
windswell fades. Seas increase quickly beginning later Sunday as
the next strong frontal system begins to impact the area.

.TIDES/COASTAL FLOODING...
As of 415 PM Wed...A perigean spring tide will bring elevated
tidal levels today through the end of the week. Minor inundation
of very low lying areas is possible around the times of
primarily the evening high tide cycles, especially near inlets
and along the beaches south of Cape Lookout tonight, then across
all of eastern NC into late week.

.MHX WATCHES/WARNINGS/ADVISORIES...
NC...Coastal Flood Advisory until midnight EDT tonight for NCZ195-
196-199.
MARINE...Small Craft Advisory from 11 AM Thursday to 2 AM EDT Saturday
for AMZ154-156.
Small Craft Advisory from 2 PM Thursday to 2 AM EDT Saturday
for AMZ152.
Small Craft Advisory from 11 AM Thursday to 8 PM EDT Friday
for AMZ158.

$$
SYNOPSIS...MHX
NEAR TERM...TL/MS
SHORT TERM...MS
LONG TERM...CB
AVIATION...TL/CB
MARINE...CB/MS
TIDES/COASTAL FLOODING...MHX

Area Forecast Discussion

National Weather Service Nashville TN

1059 PM CDT Wed Apr 8 2020

.UPDATE...
FOR EVENING DISCUSSION.

.DISCUSSION...

Updated suite of forecast products to include Severe Thunderstorm
Watch 94, which includes southern and eastern portions of mid
state region through 5 AM CDT Thursday morning. Like previously
stated, leaned toward latest HRRR model reasoning. However, that
reasoning showed convection dying off before reaching or even
moving into Nashville Metro Area. It did not show this robust
line of showers and thunderstorms that moved into the Nashville
Metro Area within the last hour and is now progressing
southeastward through I-40 Corridor of mid state region
approaching 11 PM CDT. Additional convection noted to northwest
and across southwestern Kentucky presently. This was the
convection previously noted that would develop into a squall line
of showers and thunderstorms that would move through mid state
region in association with strong cold frontal passage,
specifically through the Nashville Metro Area, around 1 AM CDT
Thursday morning, i.e. around 09/06Z. It will be of keen interest
if this present line of showers and thunderstorms progressing
southeastward through mid state region will leave an atmosphere
behind of it that will not be supportive of strong to severe
convection. As usual, tweaked hourly temperature, dewpoint, and
wind speed/direction grids. Current temperatures in line with
forecasted lows. Remainder of forecast from Thursday onward
continues to be on track.

.AVIATION...
00Z TAF DISCUSSION.

A few showers and thunderstorms moving through Middle TN as of
00Z TAF time. Don/t think any of these will hit a TAF site. Will
keep a VCTS for BNA and MQY. Might need to add this to CSV as
well. Still expecting a screaming front/squall line tonight.
Timing for CKV around 03Z...BNA/MQY around 05-06Z and CSV around
07Z. This should be a fast moving system and any storms will
contain wind/hail. The good news is the storms should be fast
moving and should only impact the TAF sites for an hour or two.
CIGs and VISs will become MVFR before the front. After the storms
move out MVFR CIGs will linger for a couple of hours before VFR
conditions return. Southwest winds cactus with the front and
switching around to the northwest post frontal with continued
gusts.

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.

DISCUSSION......JB Wright
AVIATION........12

Area Forecast Discussion...CORRECTED

National Weather Service Pueblo CO

352 PM MDT Wed Apr 8 2020

.SHORT TERM...(This evening through Thursday)
Issued at 347 PM MDT Wed Apr 8 2020

Upper ridge building over Colorado today ahead of western U.S. upper
low, keeping much of the region mild and dry, with only sporadic
breezy winds at times over the plains and across the higher peaks.
Cold front backs westward across the plains overnight, leaving a
shallow cold air mass in place along and east of the mountains by
early Thu morning. 12z/18z NAM soundings suggest stratus possible
toward sunrise on the plains as winds turn ely, though HRRR runs
have been less enthused about both the strength of the easterly
component and amount of low level saturation expected. Leaned toward
cloudier NAM at this point, though not expecting much fog/drizzle to
develop, except near where the cloud edge intersects the higher
terrain and Palmer Divide. On Thu, shallow cold air holds on across
the plains, as lee-side surface low spins up along the NM border and
resulting pressure gradient keeps an ely component to low level
winds along and east of I-25. Blended model temps from the NBM
looked rather warm over the plains, and shaded many areas downward
several degf toward cooler MAV/MET guidance. Mountains and
valleys will remain warm for another day, as clouds gradually
increase ahead of slowly approaching upper low. By late afternoon,
expect just some isolated showers to break out over the higher
terrain as upward motion increases, with best chance of measurable
precip over the higher peaks around Leadville, especially toward
early evening.

.LONG TERM...(Thursday night through Wednesday)
Issued at 347 PM MDT Wed Apr 8 2020

...Much cooler and unsettled weather expected on Sunday...

Thursday night-Friday night...Models remain in decent agreement of
northern stream upper trough digging across the central Conus on
Thursday, which continues to translate across the eastern Seaboard
on Friday, as a southern stream cut off low across southern
California slowly meanders into the Desert SW. Models also continue
to indicate a minor short wave ejecting across the Desert SW on
Thursday, will continue to translate east across the southern
Rockies Thursday night. With some increase in mid level moisture,
steep mid level lapse rates, continued low level upslope flow and
some diffluence aloft associated with the passing short wave, will
see isolated to scattered showers over the higher Thursday
afternoon spreading east across the immediate adjacent plains
Thursday evening and out across the far southeast plains Thursday
night. Snow levels are expected to remain high (aoa 9K feet) with
local accumulations of 1 to 3 inches possible at the peaks through
early Friday morning. Similar conditions can be expected for
Friday afternoon and early evening, with isolated to scattered
showers and a few possible thunderstorms over and near the higher
terrain. Temperatures through the period look to be near to
slightly above seasonal levels.

Saturday-Monday...Again, latest models in decent agreement of the
next northern stream system digging across the Intermountain West
through the day on Saturday, with increasing westerly flow aloft
keeping the southern stream cutoff low well south of the area across
southern Arizona and southern New Mexico. Saturday looks to be the
proverbial "warm before the storm" with westerly flow aloft leading
to highs in the 60s and 70s across the plains, with 50s and 60s
across the higher terrain, save for 30s and 40s at the peaks. Again,
models indicating a few possible showers across the higher terrain
Saturday afternoon, as the northern streams associated strong
cold front remains lurking just north of the Colorado and Wyoming
border Saturday evening. Well there are still some differences on
timing and strength/amplitude of this system, general model
consensus digs the strong northern stream through across the
Rockies through the day Sunday, with secondary energy digging down
the backside of the system on Monday. The system`s associated
strong cold front blasts across eastern Colorado late Saturday
night and early Sunday morning with widespread precipitation
expected over and near the higher terrain through the day Sunday
and Sunday night. Strong caa will likely lead to Sunday`s high
temperatures across the plains being recorded early Sunday
morning, with steady and cooling temperatures and gusty northerly
winds expected through the rest of the day across eastern
Colorado. Latest models indicating the potential for 3 to 6 inches
of fluffy snowfall across the central and eastern mountains
through Sunday night, with lesser amounts along the immediate
adjacent plains. Overnight lows Sunday night look to be well below
seasonal levels mainly in the teens across the lower elevations
and single digits above and below zero across the higher terrain,
with cold northwest flow aloft leading to highs on Monday well
below seasonal levels in the 20s and 30s across the eastern
plains. Secondary energy digging across the area on Monday will
also lead to scattered to numerous snow showers again, especially
over and near the higher terrain.

Tuesday-Wednesday...A cool northwest flow pattern remains in the
offing for Tuesday and Wednesday, with temperatures slowly warming
though remains below seasonal levels. Pattern also supports daily
chances of isolated to scattered showers, most numerous across the
higher terrain.

.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 347 PM MDT Wed Apr 8 2020

At KALS, VFR the next 24 hrs, with s-sw winds increasing after 17z
on Thu.

At KCOS and KPUB, VFR much of tonight, then MVFR cigs develop 10z-
12z Thu morning behind a cold front, with lower cigs persisting
through at least midday Thu. Winds will become northerly this
evening behind a cold front, then swing around to the E-SE overnight
into Thu morning.

.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...PETERSEN
LONG TERM...MW
AVIATION...PETERSEN

AREA FORECAST DISCUSSION

National Weather Service Raleigh NC

915 PM EDT Wed Apr 8 2020

.SYNOPSIS...
A cold front will approach from the west late tonight, bringing
showers and storms through Thursday morning. The cold front will
cross the area Thursday, bringing strong gusty winds. Behind this
front, high pressure will bring cooler and drier air for late
Thursday night into Saturday. Rain chances return by Sunday and
Monday as another storm system moves in from the west.

.NEAR TERM /THROUGH TONIGHT/...
As of 915 PM Wednesday...

What began as a couple of small storm clusters during the mid
afternoon over north central NC grew upscale in the hours since,
coalescing into a band of showers and strong storms which have
impacted central NC since 20z with high winds of 40-60 mph, a lot of
mostly small hail, and pockets of wind damage, feeding on steep low-
(~8.5 C/km) and mid- (~7.0-7.5 C/km) level lapse rates, moderate
MLCAPE near 1000 J/kg, and 40-50 kts of deep layer shear. This broad
broken band of showers and storms now extends across the far S
Piedmont across the Sandhills to the central/S Coastal Plain and
central Coastal Area. Outflows have largely raced out ahead of this
band but embedded discrete cells remain and will pose a continued
risk for small hail and 35+ kt wind gusts for another couple of
hours. A brief calm period will follow for much of the night with
fair to partly cloudy skies. Based on the latest CAM output and
extrapolation of upstream strong to severe convection over IN and
the Mid Miss Valley, it still appears that showers and storms are
likely to arrive in the NW CWA about 09z, crossing central NC over
the ensuing 4-5 hrs. Lows in the upper 50s to mid 60s. -GIH

Earlier discussion from 255 pm: We`ve been awaiting convective
initiation thus far, given the formidable cap around 800 mb and
dewpoints that are less than ideal, mostly in the 50s. But we`re
finally getting some agitated cu across the W Piedmont and Sandhills
where the CINH is finally dissolving and where dewpoints are
generally a bit higher than in the NE CWA, a function of the old
outflow generated from the early-morning MCS over OH/WV/VA. As
strong heating continues to chip away at the cap and culminate in
1000-1500 J/kg of MLCAPE within 30-40 kts of effective bulk shear,
we should see isolated to scattered convection develop over our far
N counties, developing further on its western flank as it propagates
to the ESE through early evening. Fat CAPE through the hail growth
zone aloft (a result of steep lapse rates through the EML, evident
in the 750-500 mb profiles in the 12z observed GSO sounding and in
proximity forecast soundings) still suggests a large hail threat,
with the wind profile indicative of possible splitting cells.
Damaging wind gusts remain a threat as well, with RAP downdraft CAPE
in the 800-1000 J/kg range. Once this activity exits the SE CWA,
likely in the late evening, we should see several hours of dry
weather and partly cloudy skies. Areas that happen to receive decent
rainfall later today could see patchy fog development, but the
presence of residual convective debris clouds to curb radiational
cooling may limit the fog threat, despite light winds. Our attention
then turns to what should be a band of strong to severe storms just
ahead of the approaching cold front over the Ohio Valley and Mid
Miss Valley tonight. Timing this convection (or its remnant MCV)
east-southeastward brings it into the western CWA toward daybreak,
so will trend pops up there very late tonight. Expect anomalously
warm lows in the upper 50s to mid 60s. -GIH

.SHORT TERM /THURSDAY/...
As of 315 PM Wednesday...

...Wind advisory may be needed for Thursday...

The band of convection is expected to cross central NC during the
morning, departing the Coastal Plain around noon or shortly
thereafter. While there may be a few embedded strong storms, the
unfavorable time of day and waning large scale forcing for ascent
will reduce the threat of strong storms. The bigger story Thu may be
the strong winds from the W and WNW near and just behind the front,
with the potential to gust to 25-35 mph as strong winds at 925-850
mb are transported groundward. Will need to monitor high-res
guidance and morning observations to see if a short-fuse wind
advisory might be warranted. (See fire weather section below for
fire concerns.) Otherwise, expect fair skies with scattered flat
stratocu. Confidence in the high temp forecast is reduced by the
likely initial delay of the coolest air by the higher terrain, as it
appears that thicknesses won`t drop in earnest until well into the
afternoon. Will go with highs from the mid 70s in the NW to the mid
80s SE. -GIH

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
As of 200 PM Wednesday...

Thursday night through Saturday night: A large upper low will swing
through SE Canada and the Northeast US Thursday night. Meanwhile at
the surface, the cold front will continue pushing east of central
NC. Expect lows in the mid 40s NW to low 50s SE in the wake of the
fropa. Cold Canadian high pressure will build south into the Plains
Thursday night and shift eastward into and over the mid-Atlantic on
Friday/Friday night. Despite a shortwave aloft passing over the the
area on the back side of the departing upper low, expect the weather
to remain dry with NW flow and subsidence over the area. Expect
below normal temperatures Friday and Friday night with highs in the
upper 50s to mid 60s and lows in the upper 30s to low 40s.
Temperatures should moderate some to near normal on Saturday and
Saturday night as the surface high shifts east off the Atlantic
coast and weak sub-tropical ridging aloft builds over the Southeast
and mid-Atlantic. Highs in the mid 60s and lows in the mid 40s to
around 50 degrees.

Sunday through Tuesday: Little change in the forecast for the system
moving into the area Sunday/Monday. The upper low should be sampled
much better today, so expect model agreement to improve further in
the next day or so. This low will slowing make its way through the
Southwest by Saturday before getting caught in a deepening northern
stream trough and swinging east through the southern Plains, then
northeast through the MS Valley as a s/w trough Sunday/Sunday night.
The wave will then lift through the OH Valley and into the Great
Lakes and Northeast US Sunday night/Monday. At the surface, the low
will strengthen as the it moves east through the Plains and MS
Valley. The attendant cold front will push east Sunday night and
Monday, though specific details regarding the timing of the front
and the evolution/track of the low are still quite uncertain. Timing
for best rainfall chances is still between 12Z Sunday and 00Z
Tuesday. This system has the potential to result in some significant
rainfall amounts across central NC. Regardless, expect some
moderation in temperatures from Sunday to Monday and increasing
moisture and cloud cover as return flow off the Atlantic and
southerly flow from the Gulf ahead of the front advect warm, moist
air into the region. Given the uncertainty and dependence on the
timing and strength of the system, will not get into specifics
regarding temperatures at this time.

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
As of 845 PM Wednesday...

Storm clusters which impacted central NC since 20z with high winds,
a lot of mostly small hail, and pockets of wind damage have
congealed into a broad broken band of showers and storms, still
impacting FAY and RWI but has pushed well SE of INT/GSO/RDU. Aside
from the continued short-term storm threat at FAY, the other
terminals will remain largely dry with VFR conditions and much
lighter winds for much of the night. We`re likely to see areas of
fog, although given the overspreading mid and high clouds,
confidence in this occurrence is low. Another band of showers and
storms will cross central NC late tonight through Thu morning,
mainly 09z to 16z, and an hour or so of MVFR cigs/vsbys are possible
at all sites during that time. VFR conditions will return from W to
E between 13z and 16z. Attention will then turn to the strong gusty
winds from the W or WNW at sustained speeds of 15-20 kts and gusts
to 25-35 kts, dominating from late morning through the afternoon,
which could generate mechanical turbulence and present difficulties
in aircraft handling, particularly smaller aircraft.

Looking beyond 00z Fri, the strong and gusty winds should subside by
early Thu evening. VFR conditions will largely hold through early
Sun as high pressure builds over the area. A storm system will
approach from the SW from midday Sun through Sun night, bringing a
high chance of stormy sub-VFR conditions. Improvement is expected
Mon as the system exits to our E. -GIH

.FIRE WEATHER...
Strong gusty winds from the W and NW are expected near and behind a
cold front that will cross central NC Thursday. These winds,
sustained at 15-20 mph with possible gusts to 25-35 mph, will occur
in conjunction with falling relative humidities, likely bottoming
out in the 25-32% range Thu afternoon as drier post-front air
spreads into the area. The combination of strong winds and low RH
will bring about concerns for adverse fire behavior, particularly in
areas that don`t see much rainfall either today or early Thu. Will
coordinate with forestry officials early Thu to address these
concerns. -GIH

.RAH WATCHES/WARNINGS/ADVISORIES...
None.

$$
SYNOPSIS...Hartfield
NEAR TERM...Hartfield
SHORT TERM...Hartfield
LONG TERM...KC
AVIATION...Hartfield
FIRE WEATHER...Hartfield

AREA FORECAST DISCUSSION

National Weather Service Charleston WV

1123 PM EDT Wed Apr 8 2020

.SYNOPSIS...
A strong cold front crosses overnight. High pressure Friday and
Saturday. Low pressure crosses Sunday/Sunday night, with a cold
front Monday morning. Cooler with weaker systems next week.

.NEAR TERM /THROUGH THURSDAY/...
As of 1120 PM Wednesday...

Tornado Watch 93 issued for all but the northern tier of the
forecast area, the northern extent of where the boundary
indicated by the west-northwest to east-southeast oriented line
of thunderstorms may get before the main line ahead of the cold
front arrives. Surface based CAPE and effective bulk shear
depict this most favored air mass for tornadic development
nicely, as do the upstream warnings.

Added severe weather wording to the forecast where the watch
is until its 08Z expiration overnight.

As of 825 PM Wednesday...

Used mostly the HRRR to time PoPs associated with a cold front
that will push through during the late overnight hours. The
timing for the strongest thunderstorms midnight to 4 AM west to
east, with a gradually weakening trend possible during that
time on loss of CAPE, which may start out over 2 KJ/kg into
southwest portions of the CWA, with elevated CAPE over 3 KJ/kg.
Bulk shear values in the 0-6 km layer are forecast to reach 50
to 60 kts giving rise to strong rotating elevated updrafts, with
large hail and damaging winds possible. The bulk shear will be
longer lived, so the wind threat is likely to outlive the hail
threat.

An isolated tornado cannot be ruled out, especially as 0-1 km
bulk shear increases to 40 kts and the LCL decreases to less
than 1km immediately ahead of the cold front. Downward transfer
of 50 to 60 kts aloft may also lead to a surge of strong wind
gusts immediately behind the front.

As of 620 PM Wednesday...

The severe thunderstorms have weakened and moved south of the
CWA. Therefore, the remainder of SVR Watch 87 has been canceled.

As of 525 PM Wednesday...

Dropped portion of SVR Watch 87 behind southward moving line.
These leaves only SW VA in the Watch.

As of 204 PM Wednesday...

Latest radar mosaic shows a broken line of showers and
thunderstorms have developed across the middle of our county
warning area. Mesoanalysis indicates these storms may be
associated with an outflow boundary from the earlier storms.

Per SPC discussion, a Severe Thunderstorm Watch has been issued
for portions of Northeast Kentucky, Southeast OH and Southwest
Virginia as well as the southern third of West Virginia until 8
PM.

Models indicate convection should wind down this evening with
a brief dry period.

A strong cold front is then expected to push southeast across
the region later tonight with the possibility of additional
strong and possibly severe storms.

The front should be southeast of the area by sunrise on
Thursday with high pressure building in. As a result,
precipitation chances will end from the northwest during the
day. Will keep chance pops in the northern mountains through the
evening hours as cold west-northwest flow prevails. Would not be
too surprised to see some snow across the highest elevations
late.

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
As of 220 PM Wednesday...

Additional shortwave will cross the area Thursday night into
Friday, with another round of precipitation, and much colder
air. Light snow showers will be likely, particularly across the
higher terrain, where light accumulations will be possible. In
addition, gusty winds on Friday will make it feel like it`s
winter again, with wind chills in the 20s to lower 30s.

High pressure will build in for Friday night into Saturday. With
a clearing sky and calm winds taking hold, widespread frost is
expected for Saturday.

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
As of 225 PM Wednesday...

After a brief break in the precipitation, rain, along with
warmer temperatures will return to the area for the start of the
long term period. Good southerly fetch of moisture will create a
good soaking rain for the area, but heaviest amounts look to lie
to the south and east of CWA. System will lift to the northeast
of the CWA at the start of next week, but mild, and somewhat
unsettled weather will continue to linger.

.AVIATION /04Z THURSDAY THROUGH MONDAY/...
As of 825 PM Wednesday...

A front stretched west to east across southern Ohio and central
WV this evening, will move northward, as a warm front, ahead of
showers and thunderstorms, associated with a cold front,
approaching from the west. These showers and thunderstorms may
be quite strong as they cross the area overnight, before
weakening during the early morning hours, as they move through
with the cold front. One last line of showers may move through
after daybreak, before clearing takes place by afternoon, except
northeast portions of WV.

The best chance for the strongest thunderstorms will be HTS,
with decreasing strength to the north and east. The timing for
strong storms is 04Z-08Z from west to east, with diminishing
strength as the storms move east.

Ceilings will lower to MVFR as the thunderstorms move through,
and may even dip briefly to IFR early Thursday morning, before
mixing through and breaking out Thursday. Even in NE WV, CKB
and EKN, where ceilings may persist throughout the day, they
should lift above MVFR early Thursday afternoon.

MVFR visibility is likely in showers and thunderstorms
overnight, with brief IFR visibility in heavier thunderstorms.

Light north surface flow will shift to south as the front moves
north tonight. Strong wind gusts are possible in the
thunderstorms overnight, mainly from the west to northwest.
Gusty west to northwest winds will develop in the wake of the
cold front Thursday, with peak gusts of 20 to 25 kts. Light west
to northwest flow aloft this evening will become light to
moderate south to southwest tonight, and then strong west as
the cold front crosses overnight, and then moderate west first
thing Thursday morning, remaining so for the balance of the day
Thursday.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Coverage of storms and associated lower
conditions and wind could vary overnight. Gusty winds Thursday
will fluctuate.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

DATE THU 04/09/20
UTC 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14
EDT 1HRLY 23 00 01 02 03 04 05 06 07 08 09 10
CRW CONSISTENCY H H H M M H H M H M H H
HTS CONSISTENCY H H M H M H H M H M M H
BKW CONSISTENCY H H H H M M M M L M H H
EKN CONSISTENCY H H H H M H L M M L M M
PKB CONSISTENCY H H M L H M M M H M M H
CKB CONSISTENCY H H H H M M H H H M H H

AFTER 06Z FRIDAY...
IFR conditions possible in showers and thunderstorms late
Sunday into Monday.

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...None.
OH...None.
KY...None.
VA...None.

$$
SYNOPSIS...JSH/SL
NEAR TERM...JSH/TRM
SHORT TERM...SL
LONG TERM...SL
AVIATION...TRM

Area Forecast Discussion

National Weather Service Shreveport LA

937 PM CDT Wed Apr 8 2020

.SHORT TERM...
Conditions this evening across the region remain very abnormally warm
and humid, with the evening sfc analysis depicting a rather large
tongue of higher theta-e air across much of Cntrl and Ern TX into
LA/Srn and Ern AR well ahead of a cold front extending from extreme SE
MO into Nrn and NW AR into SE OK into the Wrn sections of N TX. This
front remains progged to enter the NW zones of McCurtain County
OK/extreme NE TX by 06Z Thursday, before shifting S to near the I-20
corridor of E TX/N LA by 12Z, before reaching Cntrl LA into Deep E TX
by mid to late morning before the bndry pulls up stationary during the
afternoon. Convection along the front tonight remains confined to NE
AR into the Mid-South region, although the CAMs and HRRR continue to
suggest that a narrow band of convection may develop along the frontal
zone across Ern/SE AR late tonight, with consistency in the runs
indicating that any convection will remain E of ELD/MLU.

Have kept a dry forecast tonight as any moisture will remain quite
shallow and large scale forcing well to the NE of the region, although
some stratus looks to pool along and ahead of the front late tonight
mainly over portions of extreme Ern TX/N LA/Srn AR. Did bump min temps
up a tad across the warm sector given the current dewpoint trends, and
the expected stratus development as well as a thickening cirrus shield
that will increase from the W overnight. Have also beefed up the sky
conditions to mostly cloudy late tonight through Thursday especially
for the increase in elevated cloud cover well ahead of the embedded
shortwave energy that will eject E over the Srn Plains. Did trim back
pops slightly across Lower E TX/Wrn LA as well given the consensus in
the progs with the column having to saturate from the top down in the
drier post-frontal air which will continue to deepen throughout the
day.

Zone update already out...grids will be available shortly.

.PREV DISCUSSION... /issued 658 PM CDT Wed Apr 8 2020/

AVIATION...
VFR conditions will continue this evening, with a sct cu field
persisting across portions of extreme Ern TX/N LA/Srn AR, but low
MVFR/IFR cigs are expected to develop by/shortly after 06Z
Thursday over portions of Srn AR/N LA/extreme Ern TX, near and
ahead of a cold front that will enter SW AR/extreme NE TX after
08Z, and shifts N to near the I-20 corridor of E TX/N LA around
12Z. These low cigs will quickly lift/scatter out with the fropa,
with VFR conditions returning by mid to late morning as the front
enters Cntrl LA into Deep E TX. The cirrus shield will increase
and thicken from W to E late tonight/Thursday morning even in wake
of the fropa, although some cu may linger across the W/SW sections
of E TX. An approaching shortwave trough over WCntrl and Cntrl TX
Thursday after will result in increasing convection near and S of
the front as it becomes stationary, with some areas of elevated
-SHRA with embedded deeper convection developing during the
afternoon over Cntrl TX and will advance E and possibly affect
the WSW sections of E TX between 21-24Z. Have added VCSH for the
LFK terminal for mid-afternoon, with the elevated SHRA spreading
E across much of Lower E TX and N LA during the evening. SW winds
4-8kts this evening will become NNE and increase to 10-15kts with
gusts to 20kts with the fropa late tonight/Thursday morning. /15/

.PRELIMINARY POINT TEMPS/POPS...
SHV 67 78 54 69 / 0 10 40 10
MLU 66 76 52 66 / 10 10 20 10
DEQ 58 74 49 66 / 0 0 10 0
TXK 61 73 51 65 / 0 0 20 0
ELD 62 74 50 65 / 10 0 20 0
TYR 66 77 54 69 / 0 30 40 10
GGG 67 78 54 69 / 0 20 40 10
LFK 71 81 57 72 / 10 50 60 20

.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&