Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/28/18
Area Forecast Discussion
National Weather Service Burlington VT
1036 PM EDT Thu Sep 27 2018
.SYNOPSIS...
High pressure over the Northeast today will slide off the eastern
seaboard tonight making way for a disturbance aloft and weak low
pressure at the surface to bring a period of light rain to the
region late tonight into Friday morning. A decaying cold front will
bring another chance for showers Friday night into Saturday morning,
before high pressure returns for the remainder of the weekend.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
As of 1022 PM EDT Thursday...An upper level shortwave is
progressing northeastward this evening, with enhanced cloudiness
as the feature travels along an impressive longwave trough.
Radar imagery indicates there is water overhead, but dry mid-
level air appears to be impeding precipitation. The 00Z Albany
sounding and RAP forecast soundings depict it quite well. Most
precipitation on radar at this time is virga with Albany finally
reporting a trace despite reflectivities of 45dbz. Most
stations near reflectivities are reporting a trace or nothing at
all. Given this trend, it may take some more time for the
precipitation to reach surface across our area until this dry
layer is removed. High end chance to likely pops will mainly be
possible between 06Z and 10Z, and then quickly decrease from
north to south, but perhaps lingering near Springfield, VT.
Rainfall amounts will generally be 0.25" or less with the
highest amounts along southern Vermont and about 0.10" or less
from Burlington northward. However, this could still be generous
if dry mid-level air takes longer to saturate than anticipated.
.PREVIOUS DISCUSSION...
Morning clouds tend to slowly break up during the day Friday
with some more significant clearing likely around sunset through
midnight, especially across eastern areas, before a decaying
cold front dropping southeastward through Ontario encroaches
upon the region early Saturday morning. Right now it appears the
associated moisture will go more towards increased cloud cover
rather than precipitation with the best mid/upper level forcing
pulling north of the region. Will continue to highlight chance
pops for north/northwestern areas will lower chance for precip
central/southeast.
Temps through the period will be close to normal with lows both
nights in the mid 40s to mid 50s, and highs tomorrow will generally
warm into the low/mid 60s except south/central VT where temps won`t
budge out of the 50s due to lingering precip in the morning.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
As of 332 PM EDT Thursday...Not too many changes from the previous
forecast for Saturday through Saturday night. The approaching cold
front will be exiting east Saturday morning, ushering in cold air in
its wake. Surface high pressure builds in behind it, but upper level
cyclone flow remains in place with 850mb temperatures dropping
slightly throughout the day. This will allow a slight chance for
some lingering showers during the daytime on Saturday, primarily
across the high terrain and the Northeast Kingdom of VT.
Temperatures will be in the 50s to low 60s across the area, with
highs in the 40s at higher elevation. Overnight lows will be
seasonable for this time of year, with high level clouds advecting
eastward limiting the available time to radiate out completely.
Expect valley locations in the 40s and higher terrain locations (and
NE Kingdom) in the low to mid 30s.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 332 PM EDT Thursday...For those who enjoy sunshine, you will
need to look elsewhere because the extended period will likely be a
disappointment. Cool and unsettled is the theme beginning Sunday
night as our first of several impulses stream across the area.
Overall, thinking has not changed much as we will be situated
between the broad upper-level trough across the northern tier of the
US and a strong upper-level ridge building in over the southern US.
This will place us in a favorable (and somewhat stationary)
baroclinic zone between these two airmasses. Overall model consensus
through 96-hr is in good agreement with the position of the upper-
level Canadian trough and subtropical ridge across the southern US.
After Tuesday, model spread increases and uncertainty grows with how
quickly the ridge breaks down and what the downstream response will
be of the two lows nearing the US west coast. Temperatures through
the period look seasonable with highs mainly in the 60s across the
area, and lows in the 40s and 50s.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
Through 00Z Saturday...VFR conditions are expected for the next
several hours. Advancing moisture will allow clouds to thicken
and lower as the night progresses with SHRA over all TAF sites except
KMSS by 06 or 07Z. MVFR ceilings generally 2500 to 3500ft agl
and visibilities of 4SM to 6SM will be possible as showers
spread across the region. VFR conditions will gradually return
towards 12 to 13Z as showers begin to exit, except at KSLK,
KRUT, and KMPV where MVFR ceilings near 3000ft agl will remain
possible. All sites should be back to VFR by about 18Z. Winds
will be light and variable overnight, then becoming southerly
after 13Z at mostly 7kts or less.
Outlook...
Friday Night: Mainly VFR, with local IFR possible. Chance SHRA.
Saturday: Mainly VFR, with local MVFR possible. Slight chance
SHRA.
Saturday Night: VFR. NO SIG WX.
Sunday: VFR. Slight chance SHRA.
Sunday Night: Mainly VFR, with local MVFR possible. Chance SHRA.
Monday: Mainly MVFR, with local IFR possible. Chance SHRA.
Monday Night: MVFR. Chance SHRA.
Tuesday: Mainly MVFR, with local VFR possible. Chance SHRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Lahiff
NEAR TERM...Haynes/Lahiff
SHORT TERM...LaRocca
LONG TERM...LaRocca
AVIATION...Haynes
previous forecast discussion and an updated aviation discussion
are below. STP
&&
.SHORT TERM...valid for Fri and Sat...
Minimal updates to start the short term forecast period, following
morning updates increase PoPs and QPF. The latter half of the
period saw more extensive changes with the addition/expansion of
PoPs for the weekend weather system.
The cold front is pushing slowly through the region, and has
finally brought -RA to Billings. The system it timing out nicely
with HRRR at this time, which brings precip to Red Lodge between
00-02z. Snow continues to look minimal across the plains +2C
by tomorrow morning , but most of precip should be finished up
across the plains. Mountain snow becomes likely late this
evening. Winter weather advisories for the Big Horns and the
Beartooth Highway. Heaviest snow will be over the Burgess Junction
area and could see 3 to 6 inches by Friday morning.
By Friday afternoon clearing is expected to occur across the
region, but temps will remain cool Flow aloft friday evening
turns a bit more westerly which brings another disturbance across
the region.Models vary a bit on track and therefore impacts of
this weekend system. GFS keeping the majority of shower activity
north of the CWA, meanwhile the ECMWF pulls the system across the
entire CWA, bringing another good chance for precip, and possible
snow to the region into Sunday.
Highs around 50 degrees can be expected through the short term
forecast period, with lows in the 30s. AAG
.LONG TERM...valid for Sun...Mon...Tue...Wed...Thu...
An upper low will move onto the west coast late in the day
Saturday. As it moves onshore Saturday night into Sunday, it will
break apart and send a few pieces of energy across our forecast
area Sunday and Sunday night. This will bring another chance for
showers Sunday afternoon and night, although models continue to
keep the bulk of the shower activity to the north of our forecast
area across north central and northeast Montana. Temperatures will
be cold enough late Sunday into Sunday night for a possible
rain/snow mix.
Dry conditions are expected to return Monday and Tuesday as a
zonal flow aloft will move over the forecast area. By Wednesday
and Thursday, models continue to be inconsistent in bringing wet
and colder conditions across south central Montana. The latest
models keep the bulk of the precipitation across Wyoming with mild
temperatures for our area. For example, the 00z EC run last night
had 38 degrees for Billings next Thursday, but the 12z today has
60 degrees. However, the MEX guidance the past few runs has been
fairly consistent for that day with temperatures in the upper 50s
to 60s. As a result, forecaster confidence is quite low for the
middle to latter part of next week. Hooley
&&
.AVIATION...
Light rain with MVFR/IFR conditions and local LIFR will affect
south central Montana through the night including KBIL and KLVM.
Mountains will be obscured with snow in the high country and
nearby foothills. Ceilings will slowly lift after 09Z from east to
west, but look for areas of fog early Friday. BT
&&
.PRELIMINARY POINT TEMP/POPS...
Fri Sat Sun Mon Tue Wed Thu
-----------------------------------------------------------
BIL 035/049 037/049 037/048 036/064 042/062 041/060 038/059
82/W 23/W 34/W 31/B 12/W 23/W 32/W
LVM 033/046 034/052 033/047 033/063 039/062 038/060 035/058
72/W 22/W 54/W 31/B 12/W 23/W 32/W
HDN 035/050 037/051 038/051 036/065 042/064 041/061 038/061
82/W 33/W 33/W 31/B 12/W 23/W 32/W
MLS 031/051 038/051 037/047 037/062 043/064 042/061 038/059
41/B 23/W 34/W 41/B 12/W 23/W 32/W
4BQ 031/048 036/053 037/048 036/063 041/065 043/063 038/058
51/B 32/W 23/W 31/B 02/W 23/W 31/B
BHK 027/048 034/050 035/045 034/060 040/063 041/061 037/057
21/U 23/W 34/W 41/B 11/B 23/W 32/W
SHR 033/048 033/053 036/055 035/065 040/066 041/062 037/061
95/W 21/B 33/W 30/B 12/W 33/W 22/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...Winter Weather Advisory in effect until noon MDT Friday for
the Beartooth Highway FOR ZONE 67.
WY...Winter Weather Advisory in effect until 6 PM MDT Friday FOR
ZONE 98.
&&
$$
weather.gov/billings
Area Forecast Discussion
National Weather Service Charleston SC
1007 PM EDT Thu Sep 27 2018
.SYNOPSIS...
Atlantic high pressure will hold a stationary front north and
west of the region through this weekend. Then, high pressure
will gradually push a cold front through the area from the
north early next week, and this high will prevail through late
week.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
A deamplifying short wave trough moving through the TN valley
will reach the central and southern Appalachians by morning, but
becomes strung out as it is blocked by a strong deep-layered
ridge over the SW Atlantic. The associated surface stationary
front will meander from VA to northern GA through the night,
with the western edges of the sub-tropical ridge across the
area. There remains a few meso-scale boundaries from ongoing
and earlier convection, and with still modest instability, low
level moisture transport and PWat in excess of 2 inches, we
still anticipate isolated to scattered showers and t-storms
through the night. There is no longer any potential for severe
storms to occur.
The NARRE-TL is showing a medium chance of late night
fog/stratus over our inland GA counties into Allendale of SC.
But the SREF and HRRR probabilities are too low to justify
including any mention in the forecast. However, if the
convective debris clouds are able to diminish enough, due to the
wet grounds there certainly could be some locations with fog
closer to dawn.
Elevated dew points along with plenty of clouds (at least on
early) won`t allow for temps any lower than the lower or middle
70s.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
Unsettled conditions should prevail Friday through the weekend as
the region remains between a gradually retreating Atlantic ridge of
high pressure and a broad inland trough/associated surface high
pressure which will slowly push a baroclinic zone/axis of enhanced
moisture toward the Southeast coast. Friday, expect coverage of
shower/thunderstorms similar to that of Thursday afternoon/evening,
with scattered/chance PoPs in order as the deepest moisture remains
displaced west/northwest of the region. However, organized
thunderstorms could develop upstream and push into the region with
locally greater PoPs especially Friday afternoon and Friday evening.
Saturday could become the wettest day as the axis of deepest
moisture settles into the region and supports numerous
showers/thunderstorms. Thus, likely/high chance PoPs remain in area
forecasts. Sunday, the center of high pressure will shift into the
northeast Conus, and a wedge regime will develop and expand east of
the Appalachians. This wedge will push a cold front toward the
region. Timing of this front and the associated drying remains
highly uncertain. Ongoing forecasts depict PoPs ranging from slight
chance/chance north/west to high chance/likely south/southeast.
However, a slower scenario will translate to greater precipitation
coverage over more of our area Sunday.
Another round of MLCapes as high as 2000-3000 j/kg could support a
an isolated threat for damaging thunderstorm wind gusts Friday
afternoon/evening. Saturday and Sunday, greater cloud cover should
translate to slightly lower temps/reduced instability. Through the
period, PWATs around 2 inches will support a threat for locally
heavy rainfall.
Well above normal temperatures featuring highs in the upper
980s/lower 90s and lows in the lower/mid 70s will prevail Friday.
Even Saturday, despite the potential for more clouds/precip, above
normal highs in the mid/upper 80s and lows in the 70s are expected.
Sunday, near-normal high temps in the lower/mid 80s should be
common.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
Sunday night a cold front will be across or just south of our area.
Monday high pressure over the Northeastern U.S. should slowly push
this front further south, perhaps completely out of our area.
Tuesday a second high forms near the Outer Banks of NC. This high is
forecasted to build across the Southeast on Wednesday, bringing our
area dry conditions.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
Mainly VFR through 00Z Saturday. There still could be a SHRA or
TSRA and brief flight restrictions at either site tonight, but
odds of this happening is diminishing. Only a small chance of
sub-VFR conditions due to fog and/or stratus late tonight and
early Friday. Finally, the potential for impacts due to
scattered SHRA/TSRA Friday afternoon and evening is too far in
advance to consider including at this time.
Extended Aviation Outlook: Convection associated with a series
of fronts could bring brief flight restrictions.
&&
.MARINE...
Overnight: There remains decent mixing of the low level jet
around the western side of sprawling Atlantic high pressure to
produce S-SW winds as high as 13-18 kt, and seas as large as 3
or 4 ft. Isolated to scattered t-storms are expected, a few of
which still could be strong.
Thunderstorms will produce locally hazardous conditions through this
weekend. Outside thunderstorms, winds/seas will remain below SCA
levels through Sunday. Then, in the wake of a cold front, a wedge of
high pressure will build into the region from the north/northeast
early next week, and northeast winds will increase. Meanwhile,
elevated swells as high as 6-7 feet originating from Post-Tropical
Cyclone Leslie over the central Atlantic will push into our waters
by early next week. The combination of elevated winds and combined
seas could prompt Small Craft Advisories next week.
Rip Currents: A distant Leslie could send long period swell to our
beaches later this weekend into next week. This swell could
produce an enhanced risk for rip currents.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.
&&
$$
NEAR TERM...NED
SHORT TERM...SPR
LONG TERM...
AVIATION...
MARINE...
Area Forecast Discussion
National Weather Service Dodge City KS
1010 PM CDT Thu Sep 27 2018
...UPDATE TO SYNOPSIS...
.SYNOPSIS...
Issued at 1008 PM CDT Thu Sep 27 2018
WV imagery indicates a northwest flow aloft prevailing across the
Western High Plains. Near the surface, a cold front is sinking
southward across northeast Colorado and southwest Nebraska.
&&
.SHORT TERM...(This evening through Friday)
Issued at 1225 PM CDT Thu Sep 27 2018
A large upper level trough in the northern plains will start to
move southward through tonight. A strong cold front will start to
enter the northern zones shortly before sunrise and then blast
through the rest of the forecast area by noon. Latest HRRR hints
at the front coming in earlier than other models have shown over
the previous several days and as a result I tended to go with the
idea of the colder air coming in soon for temperatures and cloud
arrival. It`s reasonable to expect that our high temperature for
Friday will occur sometime during the early to mid morning for
most of the forecast area with the exception of the far southeast.
Once the front moves through stratus clouds will quickly cover the
sky which will allow steady to slowly falling temperatures during
the day. Drizzle looks to be the primary precip. Good isentropic
lift combining with a saturated layer up through the lowest 1-2
km, a dry dendritic zone, and shear just above the saturated
layer should make for an efficient drizzle environment.
.LONG TERM...(Friday night through Thursday)
Issued at 146 PM CDT Thu Sep 27 2018
Continuing the trend from the short term will be widespread areas
of light drizzle to start the forecast Friday night. A warm front
lifting northward through the night combining with modest MUCAPE
values from soundings at around 1000 J/kg and isentropic lift
could produce some rain showers or even an isolated storm or two.
Drizzle, light rain, and stratus clouds should slowly move out
from west to east from mid Saturday morning to mid Saturday
afternoon.
Sunday the newest long term models are still suggesting a warm day
across the area with the potential for mid to upper 80s for much
of the forecast area. It will be a good thirty degree jump from
Friday. An area of low pressure will move out of eastern Colorado
into western Kansas with a weaker cold front that may help in some
compressional heating as well. Winds ahead of the front should
also pick up and the stronger winds will be the trend into early
next week.
Monday through Wednesday will be warm, dry, and windy in the
afternoon as we`ll be under an upper level ridge.
Thursday will be the next area of monitoring as an upper level low
will be slowly moving from California into the desert southwest.
GFS has it moving quicker while the Euro hangs it up in California
for the time being. No real confidence in what will happen but
this would be the type of pattern if it comes to fruition for good
chances of rain and even some storms.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 542 PM CDT Thu Sep 27 2018
VFR conditions will prevail overnight with winds from the south to
southeast at less than 10 knots. A cold front will then move
through the area around sunrise shifting winds to the northeast
and increasing to around 20 knots with gusts around 30 knots into
the early afternoon. A stratus deck will also develop behind this
front creating MVFR to IFR ceilings.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 51 56 46 76 / 0 30 40 20
GCK 48 51 44 77 / 0 30 40 10
EHA 51 54 44 83 / 0 30 40 0
LBL 52 58 45 82 / 0 30 30 10
HYS 47 53 44 69 / 0 30 40 30
P28 54 67 50 75 / 0 30 50 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JJohnson
SHORT TERM...Tatro
LONG TERM...Tatro
AVIATION...Hovorka_42
Area Forecast Discussion
National Weather Service Glasgow MT
824 PM MDT Thu Sep 27 2018
.DISCUSSION...
Evening Update...
Temperatures are starting to rapidly drop as skies clear out from
north to south. The latest RAP guidance has the best handle on
this and takes temperatures into the middle 20s across a
widespread area tonight, with even some upper teens in the
typically colder spots near the Canadian border. Have therefore
gone ahead and lowered temperatures a few degrees area wide
tonight. Most of the precipitation is already out of the area and
clear skies will continue to push in from the north tonight.
-Mottice
Previous discussion...
Cold front from southern Saskatchewan will continue to
push the current area of rain further southward through the region
this evening and tonight. Accumulations of 0.10 to 0.25 of an
inch of rain are expected through western and southern portions of
our CWA. As these chances for rain diminish overnight tonight,
the colder air from the north may just barely change the rain over
to snow for a few locations - perhaps the higher elevations -
before the precipitation is all over early Friday morning over
central and southern Montana.
Over the next several days, the colder Canadian air will remain in
control over our area, while the warmer air from the south
continues to try and push north toward our area, but to no great
avail.
Model agreement is great tonight, then fairly good through this
weekend, then not so good beginning next week.
The next storm system coming into our region after tonight will be from
the west and southwest on Sunday, due to some short wave low
trough energy from the Canadian Rockies. Just enough cold air will
be in place early Sunday and late Sunday to allow some of that
rain to change over snow.
For early Sunday through early Monday, current thought is that a
trace up to half an inch of snow will be possible for our northern
tier zones and the higher elevations of Garfield County, while
around an inch of snow will be possible for Zortman and the Little
Rocky Mountains.
Beyond Monday, forecast confidence diminishes greatly regarding
how the approaching western low pressure trough interacts with the
remnants of tropical storm Rosa. Over the last few days
deterministic model data for precipitation has been highly
variable.
BMickelson
&&
.AVIATION...
VFR conditions will prevail at the TAF sites.
Clear skies will continue to move in from the north tonight with
generally light and variable winds expected through the forecast
period.
-Mottice
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
weather.gov/glasgow
Area Forecast Discussion
National Weather Service Hastings NE
652 PM CDT Thu Sep 27 2018
.SHORT TERM...(This evening through Friday)
Issued at 243 PM CDT Thu Sep 27 2018
Aloft: RAP dynamic tropopause analyses and aircraft obs revealed
NW flow over the Cntrl Plns. The mean trof axis was over the mid
MS Vly and extended SW across TX. A Rex Block was over the E Pac.
A shortwave trof was over AB/SA and it will rotate thru the base
of the broad longwave trof over the Nrn Plns tonight and into the
GtLks tomorrow. As this trof misses to the N...winds will back
from NW to W tomorrow.
Surface: Low pres was over Ontario. Its associated cold front was
over the Sandhills and dropping S. This front will cross the CWA
tonight with high pres over SW Canada building in. This high will
rapidly translate SE and be over Neb by midday tomorrow.
Rest of this afternoon: Very nice most locations. Radar and sfc
obs indicate the front is just N of Phillipsburg-Red Cloud-Geneva
at 1940Z. Highs will be in the 70s...except N of Hwy 92 where
thick altocu will hold temps in the mid-upr 60s.
Tonight: Becoming cldy from N-S. Becoming windy by midnight as
well as the surging high tightens the pres grad. Could see a
little light drzl N of I-80. Temps a touch cooler than normal.
Sat: M/cldy for much of the day with the risk of a little drzl or
light rain expanding and then gradually diminishing from N-S.
Current indications are that the stratus will thin with breaks
developing as it morphs into stratocu in the afternoon...primarily
over S-cntrl Neb.
Fcst confidence is lower than normal with temps and cld cover. As
long as stratus breaks up...our temp fcst should be ok. But for
areas that might remain OVC all day...we may not be chilly enough.
Bottom line...a chilly day. Windy in the AM...but diminishing
winds in the afternoon.
.LONG TERM...(Friday night through Thursday)
Issued at 243 PM CDT Thu Sep 27 2018
Aloft: Spaghetti plots of the last 2 runs of the EC/GFS/GFS-X/
GEM/UKMET are fcstg the E Pac Rex Block to fall apart Sat. The
cut-off low portion of the block will move onshore into the Pac
NW and diminish into a weak trof. As this occurs...a new longwave
trof will develop over the E Pac. This will induce height rises
over the Ern USA as a large subtropical high forming over the SE
USA. This config will result in low-amplitude WSW flow over the
Cntrl Plns thru Tue. Wed-Thu it appears the flow will become split
as the E Pac low is fcst to move into the Desert SW and becomes
cut-off. Fairly zonal flow along the US-Can border could begin
amplifying due to a deep low over the Aleutians. That will induce
ridge formation over Wrn Canada and a trof over the Nrn Plns.
After Tue...confidence decreases because the 00Z EC ensemble mean
has the ridge still over the E Pac. So this scenario mentioned for
Wed-Thu is not a lock.
Surface: The high that will be over Neb Fri will head E of the
rgn Sat-Sun. Meanwhile...the front that moves thru today will
begin lifting back N as a warm front as a lee low forms over CO.
The front is fcst to lift back into Nrn KS Sun. The next Canadian
cold front will drop thru the CWA and merge with the warm front
...forcing it back to the S a bit. It is then fcst to become
stationary from SW-NE across KS into Mon. What is left of this
front is fcst to lift back N across the entire CWA Tue until the
next Canadian cold front arrives Wed. Another weak little low is
fcst to slide down the lee side of the Rckys Thu.
Temps: As the high departs Fri night...increasing return flow
should advect low stratus back into the CWA. There is some
potential for patchy frost N of Neb Hwy 92 after midnight. These
areas will probably be the last to see the stratus move in. Winds
will be light. Due to uncertainty with the clds...left frost out
of the fcst for now...but that could change with future fcsts.
There is significant bust potential Sat and Sun based on where the
stratus locks in...and how far N the front gets. Some areas we
may be too warm. Bottom line is much cooler than normal Sat-Sun
where it remains cldy.
Still a little cool Mon...warmer than normal Tue in the warm
sector...and even post-frontal Wed. Then back to near normal Thu.
Rain: Nothing of significance. There could be a little drzl or
light rain around Sat-Sun and possibly lingers into Mon...but most
places won`t measure .01". Possibly a few light shwrs Tue night
with the next frontal passage...but overall we cont in a very dry
pattern.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Friday)
Issued at 642 PM CDT Thu Sep 27 2018
Quiet conditions are expected this evening, before a better push
of the cold front brings in a reinforcing shot of northerly winds
and more cloud cover. Models continue to show the potential for
MVFR ceilings to develop later tonight and into tomorrow, and
can`t rule out some showers, so do have a VCSH mention going at
both sites. Gusty northerly winds also remain a possibility
starting later tonight.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&
$$
SHORT TERM...Kelley
LONG TERM...Kelley
AVIATION...ADP
Area Forecast Discussion...UPDATED
National Weather Service Chicago/Romeoville, IL
759 PM CDT Thu Sep 27 2018
.UPDATE...
759 PM CDT
While no changes to tonight`s forecast, did increase chances for
rain (mainly light) in northern locations tomorrow, namely late
morning through mid-afternoon.
A cool season look to upstream satellite imagery this evening,
with a broad longwave trough across much of Canada digging east-
southeast into the northern U.S. The associated surface cold front
is draped across northwest Wisconsin through the central Plains
and still is on course to move south through the area on Friday.
Likely to be a period of gusty winds immediately behind the front
for a few hours, probably gusting to 20 maybe even briefly 25 mph.
Upper air analysis from this evening`s weather balloon launches
shows the tight mid-level thermal gradient developing across the
Plains. A 125 kt upper level jet sampled over the Upper Rockies
will increase the mid-level frontogenesis further eastward over
the northern CWA Friday morning peaking in the early to mid
afternoon. There looks to be enough forcing on model solutions to
overcome the immediate low-level dry air, with a stretch of rain
expanding eastward over some of the area north of I-80. The
challenge is where exactly and there will likely be a sharp
gradient on the south and possibly the north too. It can be easy
to key in on the NAM or HRRR which likely have a good forecast
"mode" of evolution, but the location when driven by f-gen is
often very difficult to pin down. So have increased PoPs for
north of I-80 for now, and that includes some likely mention in
parts of north central Illinois. Rainfall amounts still look
light.
The forecast temperature spread over the CWA on Friday still
looks good, although temperatures could fall late morning into the
afternoon over northern locations during the immediate post
frontal gusty winds and especially if it is raining.
MTF
&&
.SHORT TERM...
253 PM CDT
Through Friday...
Main concern for the short term forecast period will be increasing
cloud cover and an increasing chance for some light showers as a
cold front pushes south across the region.
For the remainder of the afternoon and tonight, persistent cloud
cover is limiting temperatures into the lower to middle 60s across
the sern portions of the CWA. Across the remainder of the area,
ample sunshine will allow temperatures to reach into the upper 60s
to lower 70s. Latest satellite imagery shows cloud cover beginning
to move into far nern IL as a shortwave and sfc cold front push
south through the Upper Mississippi Valley. Expect that cloud cover
should increase through the night with winds shifting from swly to
nwly following the frontal passage. By daybreak, the front should
have pushed through the Rockford area and possibly reach the Chicago
Metro area. Weak forcing and only modest low level moisture will be
a limiting factor with respect to pcpn chances, but should be
adequate to at least carry slight chance PoPs for the far nwrn
portions of the CWA for the early morning hours. As the front
continues to push south and east through the day, some of the
guidance is suggesting a slight increase in moisture pooling arnd
the boundary coincident with the diurnal warming. So, will carry
chance PoPs, for more sct shra invof the front, though limited
moisture should keep any wetting pcpn relatively light. With the
front already moving into the nwrn portions of the CWA by daybreak
and steadily pushing south and east through the day, the greatest
diurnal warming will be over the sern portions of the CWA, where
temps should be able to reach into the middle 60s. Over the nwrn
locations, temperatures should be limited to the lower 50s.
&&
.LONG TERM...
253 PM CDT
Friday night through Thursday...
For the longer term forecast period, the guidance remains relatively
consistent in a chilly start to the weekend. A cool, dry airmass
will build in behind the cold front. Clearing skies, light winds
should allow for strong radiative cooling. With dewpoints expected
to drop into the lower 30s by Saturday morning, especially for
locations west of the Fox Valley, there will be a chance that
temperatures will drop into the lower to middle 30s, with patchy
frost likely for areas where temperatures drop into the middle 30s.
Locations south of I-80 are expected to remain a little warmer, with
lows only in the upper 30s to lower 40s and any frost is less
likely. As the high moves off to the east through the day on
Saturday, low level flow will trend to more sly, with a warm front
lifting north through the region. The longer range guidance is
coming into better agreement on the idea that the northward extent
of the front will be limited by strong high pressure building across
the Northern Plains and to the Upper Great Lakes. The warm front
should stall out invof the IL/WI border from Sunday night into early
next week. this will keep a chance for showers and a few
thunderstorms, across much of the area until through at least mid-
week until the front finally gets pushed south by the next high.
Through the period, a ridge of high pressure across the sern CONUS
will help limit any significant moisture transport into the area, so
PoPs and potential QPF should be relatively low.
&&
.AVIATION...
For the 00Z TAFs...
The main concern is with a period of rain on Friday that could
knock down ceilings and visibility into the MVFR range.
Conditions will be quiet and VFR through the night with CIGs
gradually lowering. A cold front will move across the terminals
during the morning, shifting winds to northwest. It`s possible
that there could be a period of near due north winds during the
mid to late morning, with speeds around 10 kt if it occurs. After
the northwest to possibly north winds behind the cold front,
direction will settle into a 290-310 direction along with gusts in
the 15-20 kt range, possibly a bit higher at GYY. Speeds will then
quickly diminish with sunset as high pressure overspreads the
region.
Regarding rain trends on Friday, the forcing mechanism for the
precipitation suggests that the area of rain will be rather narrow
with likely a sharp cut-off on the southern end of it. It`s
possible this cut-off could be right over the Chicago area.
There`s a bit of uncertainty on timing, though a late AM start
time appears reasonable at RFD and early PM for Chicago area
airports. Have highest confidence in prevailing -RA at RFD, with
TEMPO conditions maintained at ORD/MDW and DPA and VCSH mention at
GYY. CIGs outside of rain should be VFR and possibly even during
it, so confidence is only medium in MVFR CIGs where prevailing or
TEMPO -RA is mentioned. VSBY may drop to MVFR at times during the
rain. Conditions will quickly improve once the precip ends.
Castro
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Marquette MI
803 PM EDT Thu Sep 27 2018
.SHORT TERM...(This evening through Friday)
Issued at 419 PM EDT THU SEP 27 2018
WV imagery and RAP analysis indicated a mid/upper level ridge along
the west coast and a broad trough from Hudson Bay into the central
CONUS resulting in cyclonic westerly flow through the Upper
Mississippi Valley and nrn Great Lakes. Rain associated with a
shortwave trough and WAA/isentropic lift was exiting eastern Upper
Michigan. Another area of showers through northeast MN and wrn Lake
Superior with 700-300 qvector conv ahead of a stronger shrtwv was
advancing into wrn Upper Michigan. At the surface, a cold front
extended into nw WI from low pressure near CYQT.
Tonight, expect showers to again spread through west into central
Upper Michigan early this evening, per radar/satellite trends. Some
isolated thunder may be possible early this evening with shallow
convection given the steep low/mid level lapse rates. However, the
coverage should diminish with the loss of daytime heating and as the
stronger forcing lifts to the northeast. Sct -shra will then
increase over the west late as winds veer to the nnw behind the cold
front and instability increases (850/700 mb temps drop to 1C/-11C).
Friday, another weak shrtwv moving through the area along with the
cold air in place with the wnw flow will support sct shra that will
become a lake effect and diurnal shower hybrid during the afternoon
that will spread through the rest of west and central Upper
Michigan. Highs will remain well below normal with readings into
the upper 40s west to lower to mid 50s east and south.
.LONG TERM...(Friday night through Thursday)
Issued at 307 PM EDT THU SEP 27 2018
...Cool and unsettled weather pattern continues into next week...
Weak shortwave/q-vector convergence with deeper moisture along with
a reinforcing cold front moves early Fri evening. Despite H85
temps as low as -6c (resulting in delta t/s 16-18c) expect limited
coverage to lake effect showers behind the front into later Fri
night given strong subsidence/drying behind the shortwave and well
mixed layer blo cloud base of 3-5kft. Given wetbulb zero heights
falling blo 1000 ft, possible there could be few snow flakes mix
in with rain showers if they are occurring. Agree with previous
shift that probably will end up with little/no pcpn closer to the
shore and better coverage well into the interior w where upsloping
aids low-level moistening. Also for Fri night, if clouds scatter
out sufficiently in the interior west and central, frost/freeze
conditions could occur. Soundings indicate expansion of narrow
layer of cu/stratocu on Sat farther inland. Will be getting pretty
dry otherwise so don`t expect much for precip, except maybe on
the Keweenaw/north central in the morning hours.
High pressure ridge more overhead on Sat night but there will
already be increasing high clouds at that point. Think that will
help interior areas avoid widespread frost. Should note that we are
still issuing seasonal frost/freeze headlines through morning of Oct
1 so we could see some headlines this weekend before stopping for
the season. Low-level warm air advection pattern takes hold Sun AM
and should quickly see lowering clouds. Shortwave and associated q-
vector convergence working across Sun PM could also help to bring
some showers, but due to lingering high pressure over Manitoba and
Ontario, showers may tend to dry out while trying to expand across
Upper Michigan. Hints that better chances for rain will set up over
WI into southern Upper Michigan closer to sfc front.
Looks like north of that sfc front and more so where tighter H85
temp gradient/right entrance jet/mid level fgen forcing is located
will be main focus for multiple periods of moderate to heavy rain
Sun night through Mon night. Also could be some embedded t-storms
into far scntrl Upper Michigan on northern edge of elevated MUCAPE.
Not clear yet how far north that focused area of rain will extend
into Upper Michigan but certainly is some potential that at least
south and east sections would get clipped by heavier rain. CPC
continues to highlight much of the Upper Great Lakes for the
possibility of heavy rain late Sun into early next week.
Big differences in models/ensembles for middle of next week, though
the latest ECMWF came more into line with GFS and GEM. Could see yet
another period of moderate to heavy rain midweek or main focus may
stay over northern Plains. Some of this deep moisture, increasing
PWATS over 2 inches, may very well be from remnants of what is
currently Hurricane Rosa lurking to the south of the Baja California
peninsula. Given the differences in the models and ensembles, made
no changes to consensus for days 6-7.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 736 PM EDT THU SEP 27 2018
Unfortunately, predictability on a possibility of a reduction in
ceilings/visbys is rather low for this TAF period as hit-and-miss
showers continue to march across Upper Michigan tonight through
tomorrow. That said, the feature to watch will be the time period
when showers are most likely to develop and directly impact the
terminals, which has been denoted in the appropriate TEMPO
groups. A band of showers is currently traversing across the
western into central section of the Upper Peninsula, with KSAW
likely going to be directly impacted within the next couple of
hours. The next round should occur overnight, with vicinity
activity persisting through much of the TAF period. SW to W winds
currently will become more W to WNW on Friday.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 419 PM EDT THU SEP 27 2018
Southwest winds to 25 knots will veer northwest tonight and persist
at 15-25 knots through Friday. Another trough moving through the
area Friday night will bring an increase in westerly winds to 30
knots that will again veer to the northwest and linger into Saturday
afternoon. Winds will then remain below 25 knots through Monday.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Beach Hazards Statement until 10 PM EDT this evening for MIZ014.
Lake Superior...
None.
Lake Michigan...
Gale Warning until 8 PM EDT this evening for LMZ248-250.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...lg
MARINE...JLB
Area Forecast Discussion
National Weather Service New York NY
1033 PM EDT Thu Sep 27 2018
.SYNOPSIS...
Low pressure will move along a stalled front to the south,
passing over or just south of New York City and Long Island late
tonight into Friday, then passing to the east Friday night.
High pressure will build from the west over the weekend and then
pass offshore early next week. Another cold front will approach
during the middle of next week.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
Light rain is moving in, with an area of moderate to heavier
rain expected after midnight from west to east.
After analysis of latest higher resolution models, and
probabilistic qpf forecasts, will maintain the flash flood
watch for those locations. Did contemplate expanding the watch
to include Suffolk County and southern New London, but too many
possible solutions point to where the watch currently is in
effect.
Of note, latest HRRR run seems to be suppressed to the south
with the low track, and thus heavier rain moves across all of
LI. Assuming a low track right along the south shore of LI,
still feel heaviest rain remains NW of the low. Also, areal and
small stream headwater FFG in areas hard hit on Tuesday are both
quite low. Lows tonight will be in the 50s inland, and lower
60s in NYC and along the coast.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Guidance had signaled potential for a quick 1-2 inches of rain
late tonight into Fri morning. Heaviest rain will be driven by
strong H8-9 WAA and elevated instability, acting on a very moist
air mass with PW increasing to over 2 inches. With that
instability in place, a few tstms are also possible. The 12-km
NAM also shows potential for training of cells as the low passes
by.
There is also potential for some heavier rain well NW of NYC
(Orange/Putnam) per combo of mid level frontogenesis and/or
orographic lift, but not enough to make for a flash flood
concern.
Rain ends Friday afternoon from west to east as the low pulls
away.
Highs on Friday may not reach 60 across interior southern CT,
with lower/mid 60s expected elsewhere, per model/MOS blend. Lows
Fri night will range from around 50 inland, to the upper 50s in
NYC.
There will be a moderate rip current risk at the ocean
beaches Friday.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
A strong upper ridge over the SE US and upper low over northern
Canada will result in zonal flow over most of the northern US
this weekend. As the upper level ridge strengthens heights over
the NE will rise in response. The forecast becomes uncertain
during the middle of next week as the remnants of Rosa in the
eastern Pacific move across Baja and eventually becomes picked
up into the westerlies and races across the country.
At the sfc, high pressure builds in from the Great Lakes over
the weekend and slides offshore early next week. Dry with near
to above normal temperatures are expected this weekend. The high
slides offshore early next week, with dry and warm weather
continuing on Mon. The 12z EC has trended towards the GFS for
the middle of the week with a frontal boundary slowly dropping
southward through New England. The remnant energy of Rosa
currently appears to pass well to the north, but some of her
moisture may impact the local area as the frontal boundary moves
through. It is too early to know whether heavy rain will be
possible at this time, but needs to be monitored over the coming
days.
Temperatures will remain above normal through the middle of next
week.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
High pressure across the northeast retreats overnight as a wave
of low pressure developing across the Ohio Valley, along a
frontal boundary, deepens and track to the northeast. The low
is expected to pass south or along the south shore of Long
Island late overnight and into Friday morning. High pressure
builds in behind the low Friday afternoon.
Light rain was spreading into the region and conditions were
remaining VFR. However, conditions will gradually lower to MVFR
and then IFR. Rain will be heavy at times from around 08Z to
13Z. A rumble of thunder is also possible at that time, mainly
at the NYC terminals and across Long Island. However,
instability is marginal and with the low probability of
convection did not include in the forecast. Conditions will
improve to VFR at the western terminals late Friday afternoon.
A east, to east/southeast flow is expected overnight, with
winds generally under 10 KT. Winds will back to NE and then N
after 12Z, and eventually to NW as the low passes to the east.
Winds will quickly diminish Friday afternoon as high pressure
builds in.
.OUTLOOK FOR 00Z SATURDAY THROUGH TUESDAY...
.Friday night-Tuesday...VFR.
&&
.MARINE...
SCA for the ocean has been extended into Fri morning. Ocean seas
will remain in the 5-6 ft range tonight as E flow increases
overnight, and a few gusts up to 25 kt are possible Fri morning
just ahead of the sfc low as it passes through. There is a
chance that 5-ft seas could linger on the outer ocean waters E
of Moriches Inlet into Fri afternoon.
&&
.HYDROLOGY...
Uncertainty remains on the exact placement of bands of heavier
rainfall of up to 2 inches, most of it falling within a 1-2
hour time frame, and 1-3 hr areal/small stream FFG within the
watch area is under or within that range, so previously issued
flash flood watches remain in effect. There is a chance they
could be expanded farther east into Suffolk on Long Island per
overnight radar trends.
&&
.TIDES/COASTAL FLOODING...
With increasing easterly flow, some minor coastal flooding will
be possible across mainly the South Shore Bays and Western Long
Island Sound shorelines along Southwest Connecticut for Friday
morning/afternoon high tide cycles. However, winds should shift
around to the north right before high tide, so extent of minor
coastal flooding remains in question.
&&
.EQUIPMENT...
NYC NOAA Weather Radio Station KWO-35 (162.55 MHz) remains off
the air for an extended period of time.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Flash Flood Watch from 4 AM EDT Friday through Friday morning
for CTZ005>011.
NY...Flash Flood Watch from 4 AM EDT Friday through Friday morning
for NYZ069>075-176>179.
NJ...Flash Flood Watch from 4 AM EDT Friday through Friday morning
for NJZ002-004-006-103>108.
MARINE...Small Craft Advisory until noon EDT Friday for ANZ350-353-355.
&&
$$
SYNOPSIS...Goodman/24
NEAR TERM...Goodman/PW
SHORT TERM...Goodman
LONG TERM...24
AVIATION...19
MARINE...Goodman/24/PW
HYDROLOGY...Goodman/24
TIDES/COASTAL FLOODING...
EQUIPMENT...
Area Forecast Discussion
National Weather Service Raleigh NC
1100 PM EDT Thu Sep 27 2018
.SYNOPSIS...
A cold front has stalled across central NC this evening with
ongoing convection across the area. The front will resume a
slow southeastward trek Friday night into Saturday as high
pressure builds into the region from the north.
&&
.NEAR TERM /THROUGH FRIDAY/...
As of 1030 PM Thursday...
Main shortwave is currently across the western North Carolina
this evening with surface low pressure starting to form. A
broken line is also moving east across central North Carolina
while a stalled surface boundary remains across the Triad
(clearly seen on the 28.00 KGSO sounding). The general idea is
for the broken line to slowly weaken as it heads east away from
the main support of the shortwave. Simultaneously, the surface
low pressure will head northeast helping to drag the stalled
boundary north as well. As the shortwave heads northeast there
will be a brief period of subsidence behind the wave allowing
for a break in the precipitation Friday morning (after the
broken line falls apart). Friday afternoon the surface front
will slowly drop back to the south.
Prev Discussion->
Convective activity beginning to increase in the southwest
Piedmont and and storms are exhibiting good mid- level rotation
at this time indicative of the better sheared environment in
that area. Currently about 1500 J/kg of ML CAPE are available to
work with and about 25 kts of bulk shear. In the lowest level
the 0-1 km shear is about 15 kts at this time with 0-1 km
helicity values of 50-100 m2/s2. While this is a decent
environment for rotating storms, those low level environment
numbers are not particularly impressive and it is hard to tell
if this rotation will translate to the surface or remain
generally aloft. In general the afternoon is shaping up to have
more of the favored instability, but the best shear values
remain well to the northwest of the forecast area. These are
expected to arrive later, but by that time the instability could
be lacking. Therefore, it appears there is only a small window
for the two to phase together around 00z in the Triad.
At the surface, the cold front remains north of the forecast area
and this could remain the case for the duration of the afternoon and
evening. Later this afternoon a shortwave is expected to track
northeastward along or just ahead of the front and could provide
some extra forcing for ascent. Currently this feature appears to be
in western GA and will not arrive until after sunset. As a result
severe activity is expected to remain isolated to scattered through
the evening hours and focused north and west of US 1. With the front
staying to the north, lows this evening will remain in the mid 60s
to lower 70s.
&&
.SHORT TERM /FRIDAY NIGHT/...
As of 420 PM Thursday...
By Friday morning the front will still be lingering north of the
area but cloudy skies are expected to prevail through the day which
could keep temperatures down in the north but southern areas are
likely to break out in the afternoon causing temperatures to climb
once again into the mid to upper 80s. As the front sags slowly
southward, the US 64 corridor is likely to become convectively
active by afternoon. That being said, with less instability and
shear to work with, severe weather is not as likely as today and
therefore SPC has general thunder for the area. By Friday evening
this activity will push south and east as continental high pressure
moves in from the northwest. This may lead to a bit of an airmass
change across the northwest Piedmont by early Saturday morning with
lows in the low 60s but areas in the southeast still only bottoming
out near 70 degrees.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
As of 230 PM Thursday...
Saturday and Saturday night: Based on recent trends, would not be
surprise if the cold frontal passage Friday night/Saturday morning
is a bit slower than what models have been advertising. Given that
reasoning, could see some lingering shower activity over the
Sandhills and coastal plain counties Saturday morning, and possibly
even some isolated convective re-development during the afternoon,
in proximity to the deeper moisture axis and weak/moderate
instability gradient.
The delay in more notable sfc pressure rises from the north until
Saturday evening will result in highs Saturday very similar to what
we see on Friday, although it should start to feel less humid across
the NW Piedmont with the arrival of lower dewpoints into the region.
Weak CAA overnight will bring slightly cooler and drier air into the
area Saturday night. Lows 60 to 65, with a few upper 50s possible in
the typically cooler spots across the northern Piedmont.
Sunday through Thursday: Subtropical ridge anchored across the
southeastern states will dominate through much of the upcoming week,
likely resulting in a prolonged period of mostly dry conditions.
The EC hints at some weak shortwave disturbances circumventing the
western/northwestern periphery of the upper ridge, reasonably close
enough to possibly result in a few showers across the western and
northern portions of the piedmont by mid to late week. However,
until this becomes more evident, with leave forecast dry for now.
The near normal temperatures Sunday and Monday, courtesy of surface
high pressure nosing down the Mid-Atlantic Seaboard and resultant
NELY low-level flow will quickly moderate, allowing temperatures to
climb back into the lower to mid 80s, a good 5 to 8 degrees above
climatology, by mid to late week.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
As of 800 PM Thursday...
Convection is currently ongoing at KRDU/ KFAY and KRWI with
widespread thunder. Also of note is how the stalled front has
crept south this evening and gone through KGSO/ KINT. Behind the
front a IFR and LIFR deck has moved in with winds turning from
the northeast. As the batch of convection moves east this
evening a secondary round of showers and thunderstorms can be
seen right behind in association with the primary shortwave. The
general thinking is for this broken line to continue to push
northeast and to only slowly weaken. Latest runs of the RAP
still have ample instability later this evening with plentiful
shear. The latest runs of the HRRR and RAP have the line segment
arriving for the western terminals (KINT and KGSO) around 11
PM, but given current motion and speed, an arrival between 930
and 11 PM looks more likely.
Early this morning as the segment heads east it will begin to
weaken as it becomes more removed from the primary lift. As the
surface low and affiliated upper level lift moves away a brief
break in the precipitation looks likely. The other main concern
Friday morning will be the chance of low stratus in the morning
hours. Latest GFS and NAM forecast soundings would indicate this
is likely while the HRRR and SREF aren`t as bullish. Overall the
highest confidence for low cigs looks towards KGSO and KINT or
closer to the front.
During the day Friday the cold front will slowly push southeast
with drier air taking its time making it into the area. As of
now the chance of showers and thunderstorms looks possible late
Friday, but confidence remains to low to mention this far out.
Outlook: The front will linger over central NC presenting
multiple opportunities for adverse aviation conditions through
Saturday before the bulk of the activity will shift off to the
southeast. A likely return to VFR conditions for Sunday and into
early next week.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Haines/WSS
NEAR TERM...Haines/Ellis
SHORT TERM...Ellis
LONG TERM...CBL
AVIATION...Haines
Area Forecast Discussion
National Weather Service San Angelo TX
658 PM CDT Thu Sep 27 2018
.AVIATION...
/00Z TAFS/
VFR conditions are expected to continue through the next 24 hours.
The latest HRRR hints at some MVFR stratus developing along the
I-10 corridor in the early morning hours. Confidence in this
occurring is low however given the dry airmass in place.
Otherwise, expect winds out of the south at 5-10 knots on Friday.
&&
.PREV DISCUSSION... /issued 230 PM CDT Thu Sep 27 2018/
SHORT TERM...
(Tonight and Friday)
Low clouds this morning have eroded to leave mostly sunny and cooler
conditions across West Central Texas this afternoon. Temperatures
are mostly in the low to mid 70s as of mid afternoon. Surface high
pressure shifting across the area as well, so winds have started to
swing back to the south across the western Big Country. This trend
will continue into tonight with south winds returning to most areas
by morning. Temperatures may not be quite as cool as this morning,
but still expect readings in the upper 50s and lower 60s. Warmer on
Friday as south winds increase, with highs climbing back into the
mid 80s.
LONG TERM...
(Friday Night through Thursday)
During the weekend and first part of next week, our area will be
on the western periphery of an upper level high, centered over the
southeastern CONUS. Seasonably warm and somewhat humid conditions
are expected for our area, with south-southeast winds. Carrying
low PoPs Saturday through Tuesday across the area generally
southeast of an Ozona to Brownwood line, for the possibility of
isolated to scattered showers and thunderstorms. The main
possibility would be in the afternoon and evening hours.
The aforementioned upper high is progged to expand farther west
into Texas during the middle of next week. Increased subsidence
should keep rain chances minimal for our area Wednesday and
Thursday. Little change in temperatures is expected. Just beyond
the end of this forecast (next Friday), the 12Z GFS indicates a
possibility for increased chances of showers and thunderstorms,
with the approach of an upper low and trough from the southwestern
states, and the approach of a cold front from the north. The
ECMWF keeps it dry with the upper high centered closer to our area
during that time.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 59 86 63 85 / 0 0 5 10
San Angelo 59 87 63 86 / 0 5 5 10
Junction 61 83 65 85 / 0 10 10 30
Brownwood 59 85 63 83 / 0 0 5 10
Sweetwater 61 87 64 84 / 0 0 5 10
Ozona 60 85 63 84 / 0 5 10 20
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
42