Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/27/17
Area Forecast Discussion
National Weather Service Duluth MN
620 PM CST Sun Feb 26 2017
.SHORT TERM...(This evening through Monday)
Issued at 229 PM CST Sun Feb 26 2017
The remnants of a sfc cold front and associated mid-level shortwave
trough will exit the Northland later this afternoon and early
evening. Most of the overnight hours tonight look to be dry, but
continued cold, as a sfc high pressure ridge translates through the
region. The RAP/NAM model soundings are progging a fairly dry column
tonight before another slug of low- to mid-level moisture advection
arrives by early to mid Monday morning. A push of 850-700 mb layer
warm air advection is progged to generate a swath of light snow,
mainly from just north of the Brainerd Lakes area to Grand Rapids,
and points northeast along the Iron Range into the Minnesota
Arrowhead for Monday. There is still some uncertainty regarding the
exact track of the precipitation that could develop along the warm
air advection, as well as the exact precipitation amounts. The
models have generally shifted the axis of precipitation farther
south than the previous model runs during the day Monday as model
QPF stays pretty much confined to the Brainerd Lakes/Grand Rapids
along the Iron Range corridor. The 26.12z NAM is the most bullish
with the QPF, and in turn the snow amounts, along with the CMC
model, while the GFS/ECMWF models are going drier than the NAM/CMC.
The 26.18z HRRR model was more in line with the NAM and CMC
solutions, so bumped up the QPF compared to the blended guidance
towards the NAM solution. In any case, the QPF amounts appear to be
light in the first place, so it will be difficult to get any
significant snow accumulations Monday. Up to an inch of snow is
possible, with perhaps some isolated higher amounts along the Iron
Range. Otherwise, locations south of Duluth and into northwest
Wisconsin aren`t anticipated to see any precipitation as the better
forcing stays to the north. Still, Monday should be mostly cloudy
across the Northland. Temperatures look to increase Monday as the
sfc warm front associated with the warm air advection makes its way
north, so highs ranging from the lower 30s north to the lower 40s
south are expected.
.LONG TERM...(Monday night through Sunday)
Issued at 221 PM CST Sun Feb 26 2017
Model differences are quite large right out of the gate Monday
night. They do agree on the location of an inverted surface trof
over the forecast area. They disagree on the placement and strength
of embedded pieces of energy progged to affect the region ahead of a
short wave trof in the lee of the Rockies. Disagreement with QPF
amounts and placement as well as the ECMWF is mainly dry, which is
consistent with its 00Z/26 run. The GFS has flip-flopped with its
handling of this scenario. Used a blended approach as a result.
The discrepancies grow even larger on Tuesday. Even the SREF and
GEFS ensembles disagree on the surface low evolution/strength and
the amount of QPF. Maintained a blended approach which affects
snow amounts. Tuesday night finds the models coming into a bit
better agreement with the mass fields as the surface low departs.
Some mid and upper level trofiness crosses the region with some
light QPF in northwest Wisconsin. Lake effect processes begin
Tuesday night late as the flow turns northwesterly off of Lake
Superior. Lake effect snow showers persist on Wednesday with a
brief break in the action elsewhere. There is a slight chance of
snow in the afternoon over the western edge of the forecast area
in response to the approach of a long wave trof. As this trof
departs, the next trof right behind it is negatively tilted, but
minimally affect the region. There will be a small window for snow
showers in the evening, mainly over east central Minnesota, while
the lake effect continues. Kept the chance pops for lake effect
snow along the south shore. However, drier air is mixing in with
the northwest flow and will affect snow amounts. Dry elsewhere
Thursday night and Friday with high pressure nearby. Model
differences again Friday night and Saturday with the handling of
an upper trof and its impact on the region. Used the blended
approach for pops.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 618 PM CST Sun Feb 26 2017
A weak system will slide east across the Northland overnight and
into Monday, bringing some light snow to the region. It looks like
the best chance of light snow will be from the KBRD area into the
KDLH and KHIB area. VFR conditions are largely expected but there
will be some areas of MVFR CIG`s and VSBY`s later tonight and into
Monday morning.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 12 35 24 34 / 20 20 60 70
INL 4 28 12 28 / 10 20 40 30
BRD 16 41 24 35 / 30 10 50 70
HYR 14 42 30 41 / 0 0 50 70
ASX 14 43 28 38 / 10 10 40 80
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&
$$
SHORT TERM...JTS
LONG TERM...GSF
AVIATION...DAP
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
939 PM CST Sun Feb 26 2017
.UPDATE...
The main changes to the late night forecast is to update the PoP,
QPF, and Weather grids to reflect the current radar and high
resolution models for the rest of the night. Have confined the
highest chances for precipitation to Lee, Fayette, and Lavaca
counties where storms continue to move east. The last few radar scans
show a weakening trend to these storms.
For midnight to dawn, have maintained the threat for fog across all
of South Central Texas. PoPs for this period have been reduced,
except for areas across the far northern part of the County Warning
Area from Llano to Williamson to Lee Counties. The HRRR show showers
and storms developing around 7am in this area. Other high resolution
models show isolated showers across much of South Central Texas for
the rest of the night into the first part of tomorrow. Have
maintained slight chances of precipitation to cover this.
To summarize...once the storms across Fayette and Lavaca counties
weaken it should be a quiet night for the most part, other than a showers
and the fog developing. Then around sunrise we could see a few
thunderstorms develop across the Hill Country and trek east.
&&
.PREV DISCUSSION... /ISSUED 627 PM CST Sun Feb 26 2017/
UPDATE...
Quick update to the afternoon forecast package. The main change is to
increase QPF across Guadalupe, Caldwell, Gonzales, and Bastrop
counties where the heavier showers have been moving late this
afternoon and evening. The LCRA Hydromet Gauge near Dale, Texas in
Caldwell county picked up a quick 0.53 inches of rainfall as a shower
moved over. We ahead and re-trended the hourly weather grids as well
to match current observations.
PREV DISCUSSION... /ISSUED 600 PM CST Sun Feb 26 2017/
AVIATION.../00Z_TAFS/
Some impressive convective showers with a few IC strikes have
developed just northeast of SAT to southeast of AUS. However, CG
strikes have not been observed yet as these cells are struggling to
make it past an inversion from 16-18 kft. Thus, for now have only
included VCSH at SAT/SSF through 2Z, but left VCTS in at AUS through
1Z due to close proximity of current cells before ending VCSH by 4Z.
Although there is a slight chance of TSRA this evening (particularly
at AUS) as dynamic forcing increases as the upper level disturbance
approaches, chances are too low to include at this time.
MVFR-VFR ceilings above 2000 feet persist at the I-35 TAF sites, but
these will gradually lower to IFR around 4-5Z. Patchy fog should
begin to develop towards 9Z as LIFR ceilings and visibilities occur
at some if not all of the I-35 TAF sites, with the best chances at
SAT/SSF. These LIFR-IFR conditions should persist through most of the
morning before rapidly improving to VFR between 18-20Z. DRT will
remain VFR this evening until MVFR ceilings develop after 8Z and IFR-
LIFR ceilings and visibilities move in between 10-12Z. Similar to
today, DRT should recover to VFR more quickly between 16-17Z.
PREV DISCUSSION... /ISSUED 314 PM CST Sun Feb 26 2017/
SHORT TERM (Tonight through Monday Night)...
Main highlight will be light to moderate showers that are ongoing
this afternoon and the likely development of a few thunderstorms
through the next 2-6 hours. Temperatures are expected to be well-
above normal to start off the work week tomorrow.
A shortwave trough and associated downstream geostrophic ascent is
evident in water vapor and visible satellite images with developing
upper level cirrus over Texas. Latest SPC mesoanalysis suggests
building instability across the south half of the region as cloud
breaks have allowed for greater insolation and diurnal heating. The
low-level convergence zone near I-35 is aiding light to moderate
showers as of 3pm but some stronger updraft growth could occur
through the late afternoon and evening as stability decreases
farther north in conjuction with the deeper ascent shifting across
the region. One or two strong thunderstorms can`t be ruled out with
the most likely location along and north of a Johnson City to La
Grange line. However, further destabilization of the mixed layer
still needs to take place still given evidence of the horizontal
convective rolls seen that suggest the inversion remains in-tact.
The briskly moving shortwave trough will pivot away from south-
central Texas by Monday morning but deep southwest flow will remain
over the area. Areas of widespread fog appear likely Monday morning
and will need to watch for dense fog possibilities. Once the low
clouds/fog mix out, the southwest flow will allow for well-above
normal temperatures as many areas reach into the 80s. With weak
forcing and weak instability, only a few showers are expected
tomorrow with very limited coverage.
LONG TERM (Tuesday through Sunday)...
No significant highlights in the long term impact wise outside of a
cold frontal passage on Wednesday and then increasing rain chances
once again over next weekend. Depending on evolution of next weekend
weather system, pockets of heavy rain will need to be monitored for.
A stronger longwave trough will shift across the central CONUS late
Tuesday into Wednesday that will shift a front through early
Wednesday morning. Little rain is expected with the frontal passage
at this stage given stronger dynamics remain north of the region with
only limited instability given the early morning passage. Much drier
air will shift into the region by late Wednesday and much cooler
temperatures into the 30s for lows are expected Thursday morning.
Will need to watch cirrus clouds closely Thursday morning. If they
clear out sooner, a light patchy freeze could be possible across the
Hill Country.
Expecting dry conditions Friday with generally zonal flow persisting
over the region as a deep cut-off low develops off the coast of west
Mexico. Model depictions are not in very good agreement with this
system as ECMWF is much more progressive with GFS slower. Have backed
off on precipitation as both models slowed this model cycle run into
Saturday. Will need to watch closely as the cut-off low shifts slowly
this direction by late weekend as PWATs could increase ahead of its
influencing lift and pockets of heavy rain could potentially be
possible Sunday. Low confidence exists currently in this possibility.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 71 61 81 65 85 / 50 20 20 10 20
Austin Bergstrom Intl Airport 72 61 80 64 86 / 50 20 20 10 20
New Braunfels Muni Airport 73 61 81 64 85 / 50 20 20 10 20
Burnet Muni Airport 66 57 79 61 81 / 40 30 20 10 20
Del Rio Intl Airport 73 53 87 57 89 / 20 10 - - -
Georgetown Muni Airport 68 59 79 63 83 / 40 30 20 10 20
Hondo Muni Airport 77 58 85 61 88 / 20 10 10 10 10
San Marcos Muni Airport 70 61 81 64 86 / 50 20 20 10 20
La Grange - Fayette Regional 72 64 81 67 86 / 40 40 20 10 20
San Antonio Intl Airport 75 60 82 65 86 / 30 20 20 10 20
Stinson Muni Airport 81 61 82 65 87 / 30 20 10 10 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Mesoscale/Aviation...LH
Synoptic/Grids...Treadway
Public Service/Data Collection...30
Area Forecast Discussion
National Weather Service Peachtree City GA
1031 PM EST Sun Feb 26 2017
.UPDATE...
Current temps already approaching overnight lows so have therefore
made adjustments to min temps tonight. Cirrus will overspread the
CWA after midnight which should slow down the temp drop keeping
temps from bottoming out. No other changes planned.
&&
.PREV DISCUSSION... /Issued 224 PM EST Sun Feb 26 2017/
SHORT TERM /Tonight through Monday Night/...
Latest RAP analysis of the eastern half of the US shows high
pressure centered right along the spine of the Appalachians
providing for a very light wind flow over the local area. Right
around normal for the temps thus far which for this year is
seasonably cool with mostly upper 50s and lower 60s. Building high
clouds to the west but for the local area it is high and dry.
Speaking of dry...dewpoints remain in the single digits and teens
across a vast majority of the area driving the RH values in the
teens as well with current Fire Danger Statement certainly on
track.
Moisture will be on the increase through tonight and especially
into Monday as high pressure quickly shifts offshore in zonal flow
aloft allowing for good return flow off the gulf. A warm front
should setup across the deep south in response and act as the
focus along with embedded shortwaves in mid level flow for shower
development west of the area initially.
This activity will eventually translate east to affect NW GA Mon
afternoon although instability axis will remain outside these
areas such that only SHRA are expected at onset. Instability does
build through the late afternoon and into the overnight and have
included slight chance thunder for primarily the southern and
western zones. Confident in categorical pops for NW zones but much
uncertainty with models on if and how quickly this activity
translates east and south through the overnight period. Have
favored a more progressive solution for now.
Deese
LONG TERM /Tuesday through Sunday/...
Start of the long-term forecast period brings us to the last day of
February...where the synoptic pattern in the mid levels will feature
long-wave trough over the Western US/Intermountain West...with a
subtropical ridge parked over the Caribbean. This would leave the
eastern two-thirds of the US in a quasi-zonal/weakly anticyclonic
flow regime. Down at the sfc...strong high pressure centered well
offshore of the Atlantic coast will still have enough ridge
influence over the Mid-Atlantic and SE states...while low
pressure will get spun up over the Central Plains as perturbations
within long wave trough induce cyclogenesis.
Sensible weather will be somewhat disturbed on Tuesday as moist
southerly flow regime promotes persistent WAA pattern in the wake of
a warm frontal passage from Monday. GFS/Euro backing off on
QPF...but still looks like north Georgia will see at least scattered
showers during the day. Moist boundary layer looks to allow for
enough destabilization for thunderstorms /sub-severe/. Temps will
once again be well-above normal with highs 70s north 80s central
Tuesday afternoon and near 60 Tuesday night.
Wednesday and Wednesday night will be the most interesting periods
of the long-term as a cold front approaches. SPC more aggressive
with 15-30% severe weather outlook across the SE US/state of
Georgia. Will have to fine tune things the next few days...but
GFS/ECMWF consistent in bringing a strong shortwave across the
Southern Plains into the OH Valley...with associated 90kt+ mid level
jet streak spreading across this area and right entrance region open
to the SE. At the sfc...continued promotion of high theta-e air from
Gulf from southerly flow in the warm sector should allow enough
instability develop...despite cooler mid level air displaced to our
northwest. Strong SW flow aloft atop weaker S/SW surface flow should
promote strong deep layer shear /at least 40-70kts/...albeit
unidirectional. All this undoubtedly raises concern for severe
weather...but will have to wait to see if dynamics will actually
line up...which never really seems to be the true case. Strongest
forcing already seems to be displaced a little too far north and
west...but still warrants attention at this point.
Rest of extended remains dry Thursday-Saturday night under sfc high
pressure and weak NW flow aloft. Temps should be more "seasonal" in
the 60s during this time. Still evidence of moisture return just
outside of this forecast period as models continue to hint at a
southern stream trough over northern Mexico. Looks like another warm
up as well.
Kovacik
FIRE WEATHER...
While winds should be much lighter today (generally less than 10 mph)
the low dewpoints should result in afternoon min RH values in the
15-25 percent range area-wide for at least 4 hrs. Given dry
fuels...a Fire Danger Statement has been issued accordingly
&&
.AVIATION...
00Z Update...
No major changes to the previous TAF. VFR through tonight and
through most of Monday. Cirrus will increase tonight with mid
level clouds increasing during the day Monday. Lower clouds around
4500 will spread across the region late Monday afternoon with MVFR
cigs moving into the forecast area Monday evening. Scattered
showers will move into the ATL/AHN/CSG area late Monday afternoon.
Winds will be light southeast to calm tonight...then southeast 5
to 10kts Monday.
//ATL Confidence...00Z Update...
High on all elements.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
Athens 36 67 52 75 / 0 30 40 40
Atlanta 44 65 55 74 / 0 70 50 40
Blairsville 30 57 47 66 / 0 30 50 60
Cartersville 33 61 53 72 / 0 70 40 50
Columbus 44 72 57 80 / 0 30 30 20
Gainesville 40 62 51 70 / 0 70 50 50
Macon 38 74 56 82 / 0 30 40 20
Rome 37 60 52 73 / 0 70 50 60
Peachtree City 35 67 53 76 / 0 50 50 30
Vidalia 42 78 61 84 / 0 30 30 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...17
LONG TERM....26
AVIATION...17
Area Forecast Discussion
National Weather Service Green Bay WI
529 PM CST Sun Feb 26 2017
Updated aviation portion for 00Z TAF issuance
.SHORT TERM...Tonight and Monday
Issued at 220 PM CST Sun Feb 26 2017
The latest rap analysis and satellite/radar imagery show a shortwave
trough moving east towards the western shoreline of Lake Superior
while pushing a cold front across northwest Wisconsin. A band of
snow showers is accompanying the front, with some decent returns
moving towards western Vilas county. Will issue an SPS if snow
showers hold on to their current intensities and forward motion.
These snow showers will pass across north-central WI late this
afternoon, and the heaviest snow showers could drop a quick inch of
snow. Behind the front, skies clear over northern Minnesota, but
more mid and high clouds are heading our direction over the western
Dakotas. Snow shower trends is the main forecast concern through
this period.
Tonight...The cold front that is moving into northwest Wisconsin is
expected to stall over central WI by late tonight. But as shortwave
energy peels off to the northeast and mid-level heights build,
convergence along the front will weaken, which should lead to snow
showers diminishing along the front over far northern Wisconsin this
evening. Less than a half inch of additional accumulations are
expected. Thereafter, mid and high clouds will invade from the west
as winds become light. Because of the mid and high clouds overhead,
think fog potential is rather limited. Lows falling into the single
digits in the north, and into the teens to lower 20s elsewhere.
Monday...Winds turn to the south which will cause the front to
return northward through the day. Will continue to see broken mid
and high clouds overhead, thicker across the north, but low level
moisture looks too meager for any chance of precip along the front.
More mild air will accompany the southerly winds, which should boost
highs into the mid 30s in the north to middle 40s in the south.
.LONG TERM...Monday Night Through Sunday
Issued at 220 PM CST Sun Feb 26 2017
A weak surface ridge will persist into the overnight hours of
Tuesday before giving way to an approaching low pressure system
and associated upper level trough. Strong warm air advection
ahead of this system will allow rain to fall across the Fox Valley
when this system arrives with a narrow band of mixed
precipitation further north and snow in northern Wisconsin. The
exact placement of this transition zone may still vary, but as the
morning progresses and warm air continues to flow into the
region, wintry precipitation is expected to steadily shift to the
north as precipitation transitions to rain by the early
afternoon. Rain showers will then continue into the evening as the
surface system moves across the region.
Cold air advection returns overnight Tuesday into Wednesday,
bringing back a chance of wintry mix and snow. Much of Wednesday
will then feature smaller chances for additional precipitation as
the trough drags off to the east and leaves behind enough forcing
to continue active weather along the lakeshore and Fox valley.
Northern Wisconsin will also have a few snow showers during this
time as wrap around moisture enters from the north.
A brief, mostly dry period is in store for Thursday into Friday
as the next surface high pressure system moves in under an upper
level ridge. A few snow showers are possible in northern Wisconsin
as winds shift northwest. Friday into Saturday will then see the
next period of light snow showers as a shortwave riding along the
back edge of this ridge enters the region into Saturday. A
stronger low pressure system follows as an upper level trough
moves in Saturday into Sunday, but the placement of this system
is still highly uncertain this far out.
Temperatures during this period will be largely above normal
through Tuesday afternoon before a cooling trend through the rest
of the week as the ridge and high pressure system move into the
area. Temperatures then start to rise above normal once again
through the weekend as winds shift south Saturday.
&&
.AVIATION...for 00Z TAF Issuance
Issued at 529 PM CST Sun Feb 26 2017
Snow showers will diminish rapidly this evening with the loss of
daytime heating as a weak cold front tracks through northeast
Wisconsin. Otherwise VFR conditions are expected during the TAF
period as mid and high clouds arrive late tonight.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......Uhlmann
AVIATION.......Kurimski
Area Forecast Discussion
National Weather Service Jackson MS
953 PM CST Sun Feb 26 2017
...ACTIVE WEATHER EXPECTED THROUGH MID WEEK...
.UPDATE...
Updated for evening discussion.
&&
.DISCUSSION...
The latest few runs of the HRRR have been showing rain showers
start to develop in southern Louisana and move into the
southeastern portion of region in the early morning hours. An
increase to the forecasted POPs have been made to reflect this
latest development. Take note that a slight chance of thunder
can`t be ruled out for this area.
The progression of the disturbance that is currently
moving through central Arkansas and Northern Mississippi is still
timed to move through our region shortly after midnight. /12/
Prior discussion below:
Now through the day tomorrow:
It has been another very dry (in terms of humidity) day across the
region with temperatures more pleasant than yesterday as the
overall trend to above average readings has kicked back in.
Despite southeast winds at the surface, moisture has yet to return
to the boundary layer and the combination of the somewhat gusty
winds and low relative humidity is again increasing fire weather
concerns. More on the specifics of the fire concerns is mentioned
in the dedicated section below. Fortunately, fire danger will not
be a concern anytime in the near future (after this afternoon)
since starting tonight the increasing southerly flow above the
surface will be bringing back moisture from the Gulf of Mexico
quickly.
A fast-moving upper level disturbance headed at the region tonight
will be the impetus for the rapid moisture return as the
disturbance effectively shoves the nearby surface high quickly off
to the east and strengthens return flow up the Lower Mississippi
Valley. Model consensus suggests the current rash of showers
breaking out to our west will consolidate and grow this evening
into a larger complex of showers and thunderstorms, which will
then translate east into western zones before dawn. After daybreak
this convection should continue to shift east through the heart
of the region, probably anchored at the nose of maximum warmth and
moisture advection a few thousand feet above the surface (which
basically should be along the I-20 corridor). Instability
overnight into mid morning tomorrow should be based above the
surface, greatly limiting the potential for severe weather (although
some small hail is still possible in this time window over
western zones). More worrisome will be mid morning through early
afternoon tomorrow as there will likely be an outflow boundary
laid down over southern zones by the main convection where non-
negligible surface-based instability could build and help trigger
some storms more capable of severe weather. The available suite of
high resolution guidance is not in high agreement concerning
convective evolution tomorrow, but we feel over central and zones
it is still worth mentioning the potential for at least one or two
storms getting up to severe potential.
By late in the afternoon tomorrow the main upper level short wave
will be shifting to the east and subsidence in its wake should be
shutting down the threat for deep convection. Many locations,
especially over east-central MS, will have struggled to warm much
before this time, but will likely get a chance to make a run up
toward 70 degrees before the afternoon is totally done. /BB/
Monday night through next week:
We will be looking at an active period with rain chances coming for
Monday night through Wednesday night with mild temperatures.
This will be followed by dry and cool weather for Thursday through
Saturday before some rain comes back in the south on Saturday night.
The best severe potential looks to be on Wednesday with the cold
front passage. There will be some limited severe potential for
Tuesday night in the northwest.
On Monday night convection will be increasing over the northern
counties in the vicinity of the warm front and the upper level jet.
On Tuesday a midlevel trough will be pushing toward the Plains. This
will push a cold front toward the Ozarks for Tuesday night. Surface
based instability will be prevalent with lapse rates 7-8C,
increasing low level shear 35 knots and deep layer shear 60-70
knots in the delta region, showalter indices -2 to -4, vertical
totals 28-30, and most unstable CAPE around 1800 j/kg. The main
axis of the upper jet will be north of the region. However we will
have a good low level jet of around 40 to 50 knots. With warm
heights over the region we will be rather capped with the approach
of the midlevel trough, which will affect the convective coverage
in the south half. The best chance of storms will be in the
northwest for Tuesday night with the approach of the system. SPC
has a marginal risk for severe storms over our northwest Delta
region with a slight risk just to our northwest. With this in
mind will keep a limited severe threat graphic for the northwest
Delta region with the approaching system for Tuesday night. The
primary risks will be damaging winds, and hail.
On Wednesday the midlevel trough will be pushing toward the
region from the Plains. This will send a cold front into the
region. Ahead of the cold front we will have low level shear 30-40
knots, deep layer shear 60-70 knots, storm relative helicity of
200-300, VT 28- 30, and showalters -2 to -4. This will be enough
for some tornado potential across the region ahead of the cold
front. SPC has put a 30 percent risk for our northern counties and
a 15 percent risk elsewhere. So with this in mind will keep the
Elevated risk across the north and limited risk across the central
and south. So will keep the primary risk being damaging winds,
hail and a tornado can not be ruled out. Conditions look to favor
a squall line to develop along the frontal boundary as it sweep
across the region with some damaging winds. The front will sweep
across most of the region by Wednesday night. Models were still
having some timing issues with the frontal passage. The rains will
end from the northwest in the wake of the front on Wednesday
night. Cool High pressure will build in from the plains on
Thursday into Friday. On Saturday high pressure will track east of
the region which will bring back southerly low level return flow.
Pwats will increase from the west to around one inch, which will
help some isolated showers to develop across the south on Saturday
night.
As far as temperatures are concerned we will be looking at a
warming trend as we push through the work week with highs peaking
at the upper 70s to the lower 80s on Tuesday. Lows will rise to
the 60s by Tuesday night. In the wake of the cold front highs will
be in the 60s for Thursday through Saturday. Lows will dip into
the 40s for Wednesday night then 30s and 40s for Thursday night
and Friday night. Lows will recover into the 40s and 50s for
Saturday night.
Looking into Sunday into early next week it looks like our rain
chances will spread across the region on Sunday into Monday. This
will be associated with an strong upper trough to the north which
will drag a cold front through for early next week./17/
&&
.AVIATION...
00Z TAF discussion:
The worst aviation conditions will be associated with a complex of
SHRA/TSRA expected to move into the GLH/GWO area after 06z and
eventually develop southward through the entire area as we go past
daybreak and into the early afternoon. Expect IFR/MVFR categories
to be prominent at most sites during this time with some
improvement possible during the mid/late afternoon. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
Jackson 52 72 63 81 / 66 81 23 20
Meridian 47 70 61 79 / 43 81 23 20
Vicksburg 54 74 64 82 / 66 90 25 23
Hattiesburg 49 75 63 81 / 39 66 16 12
Natchez 57 77 66 82 / 51 74 18 20
Greenville 50 68 62 78 / 88 70 45 34
Greenwood 49 67 61 80 / 79 87 44 33
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...None.
LA...None.
AR...None.
&&
$$
12/17/EC
Area Forecast Discussion
National Weather Service Shreveport LA
931 PM CST Sun Feb 26 2017
.UPDATE...
Warm front as OF 03z was located near a Sulphur Springs...
Mount Pleasant Texas to El Dorado Arkansas line. This feature
should continue to slowly move north overnight but for the update
this evening...lowered temps a degree or two as fcst mins had
either already been reached or were close to being reached
compared to the warm sector south of the warm front across the
southern two thirds of Northeast Texas and Northern Louisiana.
Upper flow continues to be from the southwest this evening with an
embedded shortwave located across the Upper Red River Valley of
Southwest Oklahoma and Northwest Texas. This trough will open up
in the Middle Red River Valley of Southeast Oklahoma and Western
Arkansas towards sunrise. As of late this evening...most of the
rainfall has remained near and to the north of the I-30 corridor
but as we go through the remainder of the night and as the trough
from the northwest nears, we should begin to see this more
scattered to numerous precip coverage move south and east towards
the I-20 corridor of Northeast Texas into Northern Louisiana.
Therefore left the pop forecast as it is but did lower our
extreme southern zones a precip category as the newest 00z NAM and
HRRR output suggests our southern zones may not see much in the
way of coverage until near or just after sunrise.
All other elements in pretty good shape so no further update was
necessary. Updated package already sent.
13
&&
.PREV DISCUSSION... /issued 627 PM CST Sun Feb 26 2017/
AVIATION...
For the 27/00Z TAFs, VFR conditions are still holding despite cigs
lowering in areas with showers and thunderstorms. Convection is
best handled with TEMPO conditions early in the period but should
become more widespread overnight and through Monday morning as an
upper level disturbance shifts eastward across TX into our region.
Ceilings will likely continue to deteriorate with mostly MVFR and
occasional IFR conditions possible through much of Monday morning
as convection increases and expands farther east into the region.
Convection should begin to wane during Monday afternoon with just
isolated activity still possible through the end of the TAF cycle.
Otherwise, mainly sely winds between 5-10 kts to prevail with some
occasional higher gusts invof on convection.
/19/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 58 77 64 82 / 70 50 30 30
MLU 56 76 64 83 / 60 60 30 30
DEQ 46 69 57 76 / 70 40 30 40
TXK 49 72 61 78 / 70 50 30 40
ELD 52 72 61 80 / 70 60 30 40
TYR 59 78 63 80 / 70 50 20 40
GGG 59 77 64 81 / 70 50 20 40
LFK 61 80 65 83 / 50 50 30 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
13/19