Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/01/18
Area Forecast Discussion
National Weather Service Denver/Boulder CO
728 PM MST Wed Feb 28 2018
.UPDATE...
Issued at 715 PM MST Wed Feb 28 2018
The latest RAP analysis this evening has the mid level
trough axis over the eastern plains with weak mid level subsidence
developing spreading west to east across the cwa. There are still
some weak convective showers still occurring in the mountains and
higher foothills, with primarily virga over the I-25 corridor and
adjacent plains. Coverage should continue to decrease over the
next couple of hours. Some low level upslope as well keeping the
cloud cover anchored along the urban corridor. This will decrease
as well as the wind transitions to drainage and the airmass
continues to dry and stabilize. Current forecast looks good with
only minor adjustments planned for the grids at this time.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 221 PM MST Wed Feb 28 2018
GOES-16 water vapor shows the low center progressing eastward
across Arizona with the dry conveyor belt continuing to dig south.
The subtropical jet is in place from the SE to NW over the TX
panhandle and into the central US. Over our region a surface low
over the SE portions of the state is helping to pull moderately
strong NNE winds onto the NE plains that brought cooler air and
helping winds to gust up to 25 mph on the eastern plains. There is
modest lift over the higher terrain that is helping to bring some
light snow to the higher elevations. Echoes on radar show some
returns over the higher elevations of Larimer county with some
spilling over on the western plains. Current dew point depression
readings show up to 20 degrees so suspect most of the returns over
the lower elevations are mostly virga with little to none making
it to the ground. Do not expect any precipitation to make it
further east.
The upper trough will continue to progress eastward with
increasing subsidence behind it as ridging increases. Flow will
turn westerly helping to increase downsloping winds with the help
of a deepening lee side low and clear out any low and mid level
cloud decks. Clearing will also aid in bringing lows into the
teens and low 20s overnight with single digits possible in the
mountains. Conditions on Thursday will be mild with highs
returning to the mid 50s under mostly sunny skies.
.LONG TERM...(Thursday night through Wednesday)
Issued at 405 PM MST Wed Feb 28 2018
Thursday night there will be a chance of snow along the northern
areas of the continental divide, with accumulations to 3 inches
near Rabbit Ears Pass. Friday through Sunday, there will be
Elevated Fire Danger over the Palmer Divide area. For more
details, see the fire weather discussion below.
A disturbance will move over the higher terrain bringing chances
of snow Saturday night through into Sunday. QG lift transitions
to subsidence from southwest to northeast thought the day Sunday.
As the system moves east over the plains, rain and snow potential
will increase Sunday afternoon. Due to the speed of the system,
any accumulations are expected to be light at this point.
After the passage of the disturbance, strong subsidence and
cold air advection will bring windy conditions to the area
Monday afternoon. Gusts are expected to reach near 45 mph on the
eastern plains. Conditions should remain mostly dry with
temperature slightly above normal through the beginning of the
week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 715 PM MST Wed Feb 28 2018
Lingering virga and shallow easterly winds will keep ILS
restrictions in place around the terminals over the next couple of
hours with bkn cigs around 050 ft agl. As the wind to transitions
to a southerly drainage and the airmass stabilizes, VFR
conditions will prevail after 06z this evening.
&&
.FIRE WEATHER...
Issued at 405 PM MST Wed Feb 28 2018
The fire danger will be elevated Friday through Sunday, mainly
over the Palmer Divide area, as a system move across the forecast
area. Friday and Saturday, temperatures will be warmer with
reaching 65-70 degrees on the eastern plains. RH values will drop
into the 10 to 15 percent range due to warm, dry southwest flow.
Winds are forecast to be about 20 mph, gusting to 30 mph. Sunday,
temperatures should be a held near 60 degrees with the passage of
a cold front Sunday morning. Continued windy, but cooler on
Monday.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Cooper
SHORT TERM...Bowen
LONG TERM...Sullivan
AVIATION...Cooper
FIRE WEATHER...Sullivan
Area Forecast Discussion
National Weather Service Dodge City KS
430 PM CST Wed Feb 28 2018
...Updated aviation section...
.SHORT TERM...(This evening through Thursday)
Issued at 307 PM CST Wed Feb 28 2018
The water vapor loop and RAP analysis this afternoon revealed a
positively tilted trough axis from upper low center in southeast
Arizona through eastern Colorado. The surface low tied to this
synoptic trough was located near Wichita. A band of low stratus
persisted north and northwest of the surface low, which resulted in
an axis of afternoon temperatures in the upper 30s to lower 40s,
including 39 at HYS at 20z. Interestingly, the strongest MSLP
gradient was displaced a bit farther north across northwest KS into
southern NE, and this will work southward this evening, promoting an
increase in north wind speeds to 15 to 20 mph with higher gusts.
There is really not much in the way of cold air behind this storm
system, as temperatures were in the lower to mid 40s across much of
Nebraska this afternoon.
For tonight, winds will remain in the 15-20 mph range through
midnight, with a gradual decrease thereafter as the center of the
surface ridge axis pushes into western KS in the 06-12z time frame.
As winds decrease 09-12z and sky clears out, we should see
temperatures drop to lower 20s for lows west of Meade to Bucklin to
Larned.
For Thursday, a very quiet weather day is in store as surface ridge
axis pushes east across Kansas. Light winds will be the end result
throughout the day at 10 mph or less. By late in the day, the far
western counties will see a bump in winds as the next lee trough
begins to develop. Shallow mixing with light winds should prevent
temperatures from spiking much, although direct insolation all day
will help push afternoon temperatures to the mid 50s for highs.
.LONG TERM...(Thursday night through Wednesday)
Issued at 307 PM CST Wed Feb 28 2018
The overarching theme in this Long Term forecast will be wind -- and
more wind. It all begins Friday as the next lee trough axis develops
over eastern Colorado. The MSLP gradient will be tight between the
departing 1033mb high to the east and the fresh 1010mb trough along
the Front Range. There was good agreement among neighboring WFOs to
load in stronger CONSMOS winds Friday through Sunday in this
pattern. Each day we will likely see sustained winds in the 25 to 35
mph range, particularly in the afternoon. This will all be in
response to developing deep upper low over the West Coast with
strong southwest flow aloft out ahead of it over the Rockies. The
wind direction will be mainly from the due south over much of
southwest Kansas, except the far western KS areas with more of a
westerly component. This means that in time, low level moisture will
begin to increase from the south, especially east of the U283
corridor. by Sunday afternoon, the ECMWF and GFS suggest upper 40s
to lower 50s dewpoints pushing up into south central KS.
The main jet core tied to the Rockies storm system will begin to
impinge on the Western Plains, deepening the surface low somewhere
across western Kansas, down to 995mb or even lower. If this same
pattern occurred 6 weeks later, we`d be likely looking at a severe
weather outbreak Sunday evening with greater moisture in place --
nevertheless, there is enough indication that isolated to scattered
strong/potentially marginally severe storms will be possible across
some portion of central Kansas. The GFS suggests this as more a
possibility than the ECMWF as it is farther south with the mid level
jet streak.
By Monday, the latest ECMWF suggests major mid-latitude cyclogenesis
across the Northern Plains, and the 700-850mb height gradient into
western KS would suggest yet another very windy day, but certainly
cooler (although not necessarily cold). It looks like that it will
not be until Tuesday at the earliest until we finally see a
relaxation of the surface winds.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 428 PM CST Wed Feb 28 2018
MVFR conditions will continue over the HYS and DDC terminals over
the next couple of hours with VFR conditions expected there after
and across the other terminals. Winds will generally be from a
northerly direction and over 15 knots overnight as another blast
of cold air enters western Kansas. Winds then decrease to below 10
knots tomorrow morning.
&&
.FIRE WEATHER...
Issued at 306 PM CST Wed Feb 28 2018
Elevated to critical fire weather conditions will be the theme
through early next week starting Friday. Very strong winds of 25 to
35 mph are forecast during the daytime hours Friday through Sunday,
and probably Monday as well. The main question will be how large of
an area will see critical RH values at or below 15 percent.
Regardless if the afternoon RH will be 15 or 20 percent, very
aggressive fire behavior will be likely over a prolonged period of
time. Nocturnal wind speeds will also be fairly strong at 20 to 30
mph Friday Night through Sunday Night. Eventually, a strong cold
front will push southeast, most likely late Sunday evening. Winds
Monday could be very intense from the northwest, should a major
cyclone develop to our north, which is growing increasingly likely.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 24 55 31 65 / 10 0 0 0
GCK 21 55 30 68 / 0 0 0 0
EHA 25 56 33 67 / 0 0 0 0
LBL 24 56 30 68 / 10 0 0 0
HYS 24 54 29 65 / 10 0 0 0
P28 29 57 28 61 / 10 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Friday afternoon through Friday evening
for KSZ061-062-074-075-084-085.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Umscheid
AVIATION...Hovorka_42
FIRE WEATHER...Umscheid
Area Forecast Discussion
National Weather Service Grand Rapids MI
944 PM EST Wed Feb 28 2018
LATEST UPDATE...
Update
.SYNOPSIS...
Issued at 330 PM EST Wed Feb 28 2018
A low pressure system will move through the lower Great Lakes region
Thursday and bring a mix of rain and snow and breezy conditions.
Accumulating snow is likely mainly near to south of Interstate 96.
Snow showers will linger Thursday evening before ending. High
pressure will bring fair weather Friday through the weekend.
&&
.UPDATE...
Issued at 917 PM EST Wed Feb 28 2018
I have made no significant adjustments to our on-going forecast.
However there are a few trend worth noting. The RAP model has
continued bring the heaviest precipitation farther north. The
HRRR is also doing this, it had the max precipitation band on the
19z run over Van Buren County, it has gone a touch farther north
with every run since then. The 01z run has it just that band much
wider and it now is just touching southern Kent County. This could
mean much heavier wet snow during the midday hours of Thursday. We
will have continue to watch trends and we may have to update the
forecast to include higher snowfall amounts. However, for now,
considering model uncertainty, I will leave the forecast as is.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 330 PM EST Wed Feb 28 2018
A low pressure system near Lafayette IN at 12Z Thursday will
continue to strengthen and move east to near PIT by 00Z Friday.
This system will bring rain and snow to our fcst area Thursday.
Significant short range and high resolution computer model guidance
discrepancies for the past several days and still today make for a
very complex and lower confidence fcst in terms of placement of
heaviest qpf and how much snow will fall.
Rain will move into our southern counties during the early morning
hours Thursday. A consensus of latest higher resolution computer
model guidance suggests that rain will gradually become mixed with
and then change over to heavy wet snow from mid to late morning
through the afternoon.
This transition will also be aided by dynamical cooling processes as
pcpn becomes heavy from mid to late morning into the afternoon. Pcpn
will become heavy as a result of vigorous mid level omegas through
the dgz in response to strong mid level frontogenetical forcing. I
expect snowfall rates of 1-2 inches per hour at times in the
heaviest frontogenetical forced mesoscale bands.
My experience tells me that given ne to north flow caa to the north
of the low track and dynamical cooling effects when heavier pcpn
moves in that p-type will transition to heavy wet snow fairly
quickly from mid to late morning into early afternoon.
So our fcst remains very consistent with our previous forecasts
from yesterday and overnight and we will continue to fcst 2 to 6
inches of snow for roughly the southern half of our fcst area.
Higher amounts are possible where strongest mid level fgen remains
most persistent. Conversely if mid level fgen is not as robust as
advertised by a consensus of latest guidance then dynamical
cooling effects will be mitigated thus potentially leading to a
longer period of rain before the transition to snow.
The heavy wet snow in conjunction with breezy conditions could
potentially combine to result in some power outages. Hazardous
travel conditions are also likely to develop later in the day
Thursday through Thursday evening as snow accumulates on roadways
and temps fall to below freezing Thursday evening.
For all of these aforementioned reasons we will issue a winter wx
advisory for our southern three tiers of counties from 14Z Thur thru
03Z Fri. Thanks for coord on headline decisions DTX/IWX.
.LONG TERM...(Friday through Wednesday)
Issued at 330 PM EST Wed Feb 28 2018
Fair weather expected through the weekend as sfc high pressure will
be in control before low pressure approaches from the Plains states
on Monday and tracks across Lower Michigan by Wednesday.
Model trends with the low are for a slower arrival of precip. Best
estimate at this time is that a quick burst of rain or mixed precip
moves through Monday night followed by dry slotting early Tuesday.
The sfc low is kept on a more easterly heading thanks to upper level
blocking across northeast Canada. The low is occluding as it moves
over Lower Michigan and could bring light snow accumulations Tuesday
night into Wednesday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 647 PM EST Wed Feb 28 2018
For the most part I expect VFR conditions this evening. The areas
of MVFR cigs should break up for a few hours this evening before
the precipitation shield from the storm moves into our TAF sites.
Timing is an issue as is the change to snow from rain. MKG appears
to be on the north edge of this storm and should have the least
amount of IFR conditions. AZO and BTL would at this point seem to
the most intense snowfall, I could see 3 to 5 hours of +SN with
gusty north winds there from late morning into mid afternoon. The
snow should move out of the TAF sites between 21z and 00z .
There is still some question just where the heaviest precipitation
will occur. The latest trend in our hourly hi-res models is to
take the precipitation farther north (RAP and HRRR). These TAFs
were written based on that idea(northward trend from RAP and HRRR).
If I used the 18z HI RES NAM MKG and GRR would have NO
precipitation at all. This seemed to be odd model and not
considered in for these TAFs.
The precipitation will start as rain for sure but there is enough
dynamic cooling to make all the precipitation snow by 15z or so.
Any of our TAF sites that gets moderate or heavy precipitation
rates will be all snow.
&&
.HYDROLOGY...
Issued at 330 PM EST Wed Feb 28 2018
River levels continue to fall with only 7 sites remaining in flood,
as of 2 PM Wednesday. River levels are forecast to fall at most
sites into Thursday.
Uncertainty exists in the precipitation forecast for tonight through
Thursday night. There is potential for some locally heavy rain, in
excess of an inch. Further uncertainty exists on Thursday and
Thursday evening when a mix with and changeover to snow is possible.
The rain could result in a slowing of the fall of river levels or
even bring back some rising river levels. A re-issuance or a
continuation of river warnings are likely.
We will be closely monitoring the evolution of the forecast and the
resultant rainfall. Given elevated stream flows in all areas, if you
live near rivers and streams pay close attention to the forecast
through Thursday.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Winter Weather Advisory from 9 AM to 10 PM EST Thursday for
MIZ056>059-064>067-071>074.
LM...None.
&&
$$
UPDATE...WDM
SYNOPSIS...Laurens
SHORT TERM...Laurens
LONG TERM...Ostuno
AVIATION...WDM
HYDROLOGY...63
Area Forecast Discussion
National Weather Service Huntsville AL
832 PM CST Wed Feb 28 2018
.NEAR TERM...(Tonight)
Issued at 832 PM CST Wed Feb 28 2018
As alluded to previously, hydrological issues will be the top item
regarding the forecast for tonight. At the present, a frontal
boundary extended in a NW-SE orientation, mainly from west of
Nashville, to west of Muscle Shoals to around Anniston. Deep
moisture is in the area, with precipitable water amounts ranging
from 1.2 to 1.3 inches, or in the +90% of climatological norms. In
addition to the lower/mid level moisture, a huge plume of higher
altitude moisture from the tropics/subtropics extended from south of
Hawaii, across the Baja and the southeastern CONUS.
Local and regional radar views indicated a seemingly endless stream
of showers approaching the Tennessee Valley from central Texas,
across the Mid South and to the Appalachians. A quick look at
movement of this activity would "suggest" that most of it will impact
areas north of this forecast area. However, output from the HRRR its
past few runs, as well as the RAP and 18Z NAM/GFS has rain from this
system affecting areas, especially near the Tennessee River and
points north. Given that the "official" sites have recorded rainfall
totals ranging from ~1.5" to 2", a few other mesonet sites have
recorded over 3" - this was mainly since midnight. This amount of
water has obviously caused all sorts of hydrological issues, ranging
from flash flooding affecting parts of northwest and north central
AL, to areal flooding over parts of NE Alabama. In addition, many of
the smaller streams and rivers across the area were running at higher
that normal levels, some at or above their respective flood stages.
Given the addtional moisture/precipitation moving in from the WSW,
more flooding issues will continue for the overnight.
We will keep the Flood Watch going at least into late Thursday
morning. An additional 1-2" of rainfall looks pretty likely for the
area into late Thu morning, with some locations (especially our far
northern AL and southern middle TN) receiving over 3" by the times
it`s all said and done.
Updates for the overnight, kept categorical rain chances going where
they are already in place. There is a sharp demarcation with somewhat
drier conditions further south of the Tennessee River. Scaled back
thunder chances from categorical to scattered, mainly for more
convection moving in late tonight.
.SHORT TERM...(Thursday through Thursday night)
Issued at 151 PM CST Wed Feb 28 2018
After a brief possible "break" in the warm frontal band rain lifting
northward, the cold front will advance southeast during the morning
hours. A band of showers and thunderstorms is likely, possibly with
a few strong storms once again. Rainfall amounts of 1-1.5 inches is
possible with this band, which likely produce short term flash
flooding in spots, and add to the existing runoff for eventual river
flooding. As such, the Flood Watch will be maintained through 6 pm
LST. Highs will still reach the lower to mid 60s, before falling only
very slowly late. The better cold advection arrives Thursday evening
with brisk north winds. Lows will easily drop into the upper 30s by
Friday morning.
.LONG TERM...(Friday through Tuesday)
Issued at 151 PM CST Wed Feb 28 2018
Temperatures will return closer to normal for the weekend as cold
air advection occurs behind the front. High temperatures will fall
into the 50s Friday, rebounding slightly to near 60 for the weekend.
However, the main focus will end up being Friday and Saturday night,
since blended and ensemble mean guidance point to a potential freeze.
Right now this looks like a mild freeze, controlled mostly by cold
air advection rather than radiational cooling, but it could hit
newly-blooming or budding plants that have taken advantage of the
recent warm weather.
Attention then turns to the next system Monday and Tuesday, a fairly
deep Pacific trough that will eject into the Great Lakes. The
greatest spread in the extended occurs here, with the GFS and CMC
families showing a more progressive, weaker, and drier solution,
whereas the ECMWF & EPS cut the low off and have it meander about the
lower Great Lakes (with much more QPF though it is still < 1 inch).
For now, the forecast will reflect the greater consensus offered by
the faster/weaker/drier GFS and CMC.
Once that system is out of the way, the rest of the forecast period
looks dry and seasonable, with highs hovering around normal and lows
in the mid 30s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 557 PM CST Wed Feb 28 2018
Inclement weather should continue for the TAF period, as plenty of
moisture, modest lift and a lingering frontal boundary create
periods of showers. While generally MVFR CIG/VIS values should
continue with shower activity, lower IFR, possibly even more reduced
CIG/VIS values could accompany the heaviest showers. Somewhat higher
instability values could bring a risk of convection with the showers
during Thu morning, preceding an approaching cold front. The passage
of this first front should result in southerly winds becoming NW in
the late morning. Light rain and MVFR CIGS ~2500 ft AGL should
continue for most of the afternoon.
&&
.HUN WATCHES/WARNINGS/ADVISORIES...
AL...Flood Watch through Thursday afternoon for ALZ001>010-016.
TN...Flood Watch through Thursday afternoon for TNZ076-096-097.
&&
$$
NEAR TERM...RSB
SHORT TERM...17
LONG TERM...BCC
AVIATION...RSB
For more information please visit our website
at weather.gov/huntsville.
Area Forecast Discussion
National Weather Service Jackson MS
613 PM CST Wed Feb 28 2018
.UPDATE...
Updated for 00Z aviation discussion
&&
.AVIATION...
00Z TAF discussion:
Most of the evening will be VFR and free from any rain, although
activity will be lurking just north of GLH/GWO. Expect low cloud
development after midnight to bring ceilings down to MVFR through
the remainder of the period. SHRA/TSRA will increase along the
GLH/GWO corridor after midnight, reach the GTR area around
daybreak, and then the JAN/HKS to MEI corridor later in the
morning. The front will pass through GLH and GWO just prior to
daybreak, and then GTR, JAN and HKS as we go through the morning.
/26/EC/
&&
.DISCUSSION...
Tonight and Thursday:
Convective band taking shape over north MS at the moment, but
should waver to the north before coming back south after midnight.
The HRRR seems to have a good handle on this with the majority of
the evening only seeing a few showers. The heavier rain will come
in after midnight as the multi level wave approaches from the
west. This precip area will be more progressive and amounts to the
south will not be as heavy as what occurs in the gradient near
the northern CWA border. There, amounts of 1 to 3 inches look
possible, depending on where the axis of heaviest rain sets up.
Some marginal risk of severe storms will exist later tonight with
the storms associated with the main frontal boundary. Although
most convection looks anafrontal, isolated severe surface based
storms may be possible at the interface of the cold/warm front.
The boundary will sweep through the forecast area after sunrise
with the precipitation ending during the afternoon from the
northwest./26/
Thursday night through next Wednesday:
With the upper trough exiting off to the east, the upper ridge over
the central CONUS begins its amplification on Friday. The ridge axis
transits eastward over the Mississippi River Valley throughout the
weekend. This pattern will allow the Valley a few days of quiet,
sunny weather that will help dry out the saturated soils. Conditions
going through the weekend will consist of near normal to just above
normal temperatures (highs in the 60s/low 70s and lows in the upper
30s/lower 40s). Skies will be clear on Friday, mostly clear of
Saturday, and then cloud cover will increase from the west on
Sunday. Monday will bring a deepening low pressure system across the
northern plains and an associated frontal boundary into the
ArkLaMiss Monday into Tuesday. At this time, instability looks weak.
PWs increase to above 1" on Monday and dewpoints will rise into the
low 60s in the warm sector. Thunder will accompany the rain with
this system but the severe potential will likely decrease as the
upper level system moves away from the moist sector. The system
exits quickly off to the east later Tuesday. Northerly flow
following this system will keep conditions with near normal
temperatures through the middle of next week. /10/
&&
.PRELIMINARY POINT TEMPS/POPS...
Jackson 67 70 45 64 / 20 85 6 1
Meridian 67 72 44 64 / 24 64 8 0
Vicksburg 65 69 44 63 / 31 80 6 1
Hattiesburg 69 76 48 68 / 30 73 11 1
Natchez 67 70 47 65 / 21 73 6 1
Greenville 59 67 42 58 / 95 95 3 0
Greenwood 60 67 41 61 / 75 97 5 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Flood Watch through Thursday morning for MSZ018-019-025-026-034.
LA...Flood Watch through Thursday morning for LAZ007.
AR...Flood Watch through Thursday morning for ARZ074-075.
&&
$$
Area Forecast Discussion
National Weather Service Jacksonville FL
719 PM EST Wed Feb 28 2018
.UPDATE...Mid cloud deck over good part of ne FL this
evening...even isolated very light showers E of Lake
City...which are expected to diminish next hour or so...
with 10 pct POP coverage for this. Otherwise partly cloudy
skies. HRRR and SREF suggest low cloudiness and patchy fog
over the western part of forecast area after midnight...
spreading NE toward JAX/SSI areas and possibly GNV area
toward dawn. Low temps will be in the lower-mid 60s.
&&
.AVIATION...VFR conditions expected through midnight. Late
Tonight, model guidance suggests some IFR CIGS may develop over
wrn FL peninsula and spread toward GNV, VQQ, JAX, and SSI TAF
sites after 08z. Primarily focused on low CIGs...but included
lower vsby for fog at GNV. Anticipate gradual clearing of low
CIGS during the mid-late morning hours Thursday.
&&
.MARINE...No significant changes planned for next CWF issuance.
South winds around 10 knots will become southwesterly early
Thursday morning, and approach SCEC levels in the offshore waters.
Winds will continue to increase to around 15 knots across all the
waters by early afternoon. Winds will shift northwesterly as a
cold front moves through the area. High pressure will build
northwest of the region Friday then north of the region this
weekend with a return of onshore flow with strong northerly flow
potentially gusting near gale force Saturday.
Rip Currents: Low risk is expected for Thursday.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 63 83 53 70 / 0 30 40 0
SSI 63 79 59 70 / 0 0 30 0
JAX 63 86 61 77 / 10 0 30 0
SGJ 64 84 62 74 / 0 0 30 10
GNV 62 84 62 78 / 0 10 30 0
OCF 63 85 64 79 / 0 0 30 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&
$$
Wolf/Sandrik
Area Forecast Discussion
National Weather Service Marquette MI
724 PM EST Wed Feb 28 2018
.SHORT TERM...(This evening through Thursday)
Issued at 405 PM EST WED FEB 28 2018
WV imagery and RAP analysis indicated a low amplitude pattern across
the CONUS with a mid/upper level trough from nrn Saskatechewan into
the nrn plains. A more vigorous srn stream shrtwv was moving from AZ
into NM. At the surface, a ridge extended from Hudson Bay into wrn
Lake Superior resulting in light nrly flow into Upper Michigan.
Vis/IR loops showed increasing mid/high clouds from the plains into
cntrl and ne WI with weak mid level fgen.
Tonight, expect gradually increasing clouds will limit radiational
cooling as min temps only fall into the mid/upper teens inland west
and the lower 20s east.
Thursday, the approach of weak/moderate 700-300 qvector conv with
the nrn stream mid level trough and inverted sfc trough will provide
the focus for some light pcpn into the wrn and far srn cwa.
However, with the weak dynamics and moisture inflow, only chance
POPs at most were mentioned. Mainly snow is expected but with only
light pcpn and temps into the mid 30s by afternoon, a mix with
rain is also possible.
.LONG TERM...(Thursday night through Wednesday)
Issued at 315 PM EST WED FEB 28 2018
Ensembles continue to demonstrate minimal spread in the longwave
pattern, with a ridge arriving across the middle CONUS and
amplifying sligthly over the Canadian Prairies then stretching to
the Great Lakes region. This ridge begins to push east late in the
extended periods with greater spread amongst ensemble solutions
towards the middle of next week.
For the shorter term periods of Thur ngt - Sat, height rises will
arrive with a departing surface trough. Precip looks to remain out
of the forecast, with a stretch of dry weather and mild temperatures
returning to the middle/upper 30s to lower 40s in a few locations.
With some melting snowpack during the daylight hours, and lighter
winds at night, it is possible some of the additional moisture could
cause patchy fog to develop. Currently there are no indications that
this could pose a problem; however, there may be some slick spots
that develop overnight.
For the second half of the weekend into early next week, relatively
quiet pattern continues. Guidance is indicating a possible low
pressure developing in the Southern Rockies Sun ngt/Mon, with an
expansive precip shield associated with this feature Mon ngt/Tue
across the middle CONUS. Temps ahead of this system will likely warm
into the upper 30s to lower 40s under strong southwest flow;
however, a frontal boundary will slip through and winds shift
north/northeast for Tue with cooler temps returning mid-week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 724 PM EST WED FEB 28 2018
Onshore, upslope flow tonight into Thu will promote low CIGs and
VIS/FG as low level moisture comes off the lake and overall moisture
increases as a couple of troughs move in. While confidence in exact
VIS/CIG is limited, decided to include poor conditions in the
forecast since all available guidance was showing something similar.
Did not go with the lowest guidance due to the limited confidence.
Worst conditions should be at KSAW due to more favorable
upslope/onshore wind component.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 405 PM EST WED FEB 28 2018
Winds are expected to remain below 25 knots through the weekend.
Southeast winds could reach 30 kts early next week as low pressure
system approaches from the northern Plains.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...JLB
LONG TERM...Beachler
AVIATION...Titus
MARINE...JLB
Area Forecast Discussion
National Weather Service San Angelo TX
242 PM CST Wed Feb 28 2018
.SHORT TERM...
(Tonight and Thursday)
Scattered showers and thunderstorms have developed the past hour
from near Throckmorton, southwest to near Sweetwater in Nolan county.
This activity is developing in advance of a dryline/Pacific front
entering far western sections. Hi-Res models including the TTU WRF
and HRRR seem to be initializing this convection quite well and
indicate additional development east and southeast through evening
as the dryline/Pacific front push east and large scale ascent
increases with the approaching upper level trough. Strong shear,
coupled with moderate instability should result in a few strong to
severe storms mainly this evening when large-scale ascent increases.
The most favored area for a few severe storms will be east of an
Albany, Ballinger to Junction line this evening, with large hail
and damaging winds possible. Precipitation is expected to end over
far southeast counties shortly after midnight as the Pacific front
clears the area.
A stronger cold front will drop south across the area overnight
and early Thursday. Gusty north winds will develop behind the front
Thursday morning, with winds diminishing during the afternoon hours.
Skies will be sunny but temperatures will be cooler, with afternoon
highs in the 60s.
.LONG TERM...
(Thursday night through Wednesday)
The next in a series of intense upper level short waves will move
across the central and southern Plains on Sunday and Monday. Looks
like most of the upper level support will remain north of West
Central Texas. However, the upper system will drag a cold
front/dryline across West Central Sunday and Sunday night. There be
enough low level moisture and instability for isolated to scattered
showers and thunderstorms along the front Sunday and Sunday night,
with a few storms over the southeast part of the area Monday
morning. The best chance for storms looks to be across the eastern
1/3 of the area. Going with a dry forecast through the remainder of
the long term forecast. expect temperatures to be above normal, 75
to 80 for highs on Sunday due to decent low level southerly flow.
Lows will be in the 30s Thursday night and Sunday night and mainly
40s to lower 50s through the rest of the long term forecast.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 44 61 35 67 / 30 0 0 0
San Angelo 45 65 35 70 / 10 0 0 0
Junction 46 66 36 69 / 40 0 0 0
Brownwood 47 62 34 66 / 60 0 0 5
Sweetwater 42 62 36 67 / 5 0 0 0
Ozona 46 66 36 68 / 10 0 0 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
21/24