Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/17/17
Area Forecast Discussion
National Weather Service Charleston SC
935 PM EST Mon Jan 16 2017
.SYNOPSIS...
High pressure will extend across the area through tonight. A
front will stall across the area on Wednesday, then lift north
as a warm front Thursday night. Another cold front will affect
the area on Sunday.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Late this evening: No change to the going forecast. The latest
runs of the HRRR and RAP have been consistent showing fog expand
after midnight across the entire forecast area. To some degree,
this appears to be already be underway. Areas along the coast
are seeing at least periodic low ceilings and visibilities
moving onshore associated with sea fog over the coastal waters.
Meanwhile, locations across the Midlands are beginning to
experience fog (some dense). So, it will likely be some
combination of advection sea fog and inland radiation fog. Dense
fog advisories remain a distinct possibility depending on how
the fog evolves overnight.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
A deep layered ridge will maintain warm and dry conditions on
Tuesday with high temps in the mid to upper 70s. A flattening
upper level flow and a weak shortwave pushing east will favor a
weak back door cold front sinking into the area on Wednesday.
Although mostly cloudy skies will result, the subsidence
resulting from the WNW low-level flow and limited moisture
advection should limit rain potential as the front moves in.
Pre-frontal compression and downslope flow will produce another
warm day in the mid 70s. Thursday should again be mostly dry and
fairly warm though weaker downslope flow will yield highs a few
degrees lower than Wednesday.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Medium range guidance agrees that the axis of long wave H5
ridge will ripple over the region on Thursday. However, the sfc
front is expected to slowly lift north as a weak warm front.
PoPs across the forecast area will remain limited to SCHC, with
values slowly lowering from south to north. High temperatures on
Thursday are forecast to favor values around 70 degrees over
land.
Thursday night into Friday, a negatively tilted H5 trough is will
pass over the southern Appalachians, brushing the CWA with weak
omega by sunrise Fri. The combination of deep moisture, weak
instability, and weak forcing should support sct showers. In the
wake of the front, dry air will spread across the region Sat am.
Saturday night into Sunday, a large low pressure system will
organize over the Great Plains, tracking over the Mid West by Sunday
evening. Moist SW flow will gradually increase across the forecast
through the late weekend. In fact, moist and warm llvl flow may
develop a band of sfc based CAPE as high as 1000 J/kg on Sunday. I
will increase PoPs to likely, for showers and thunderstorms. The
center of the H5 low is expected to pass over the mid Atlantic
region, with wrap around moisture crossing the CWA. SCHC showers and
near normal highs expected on Monday.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
Difficult forecast for both terminals overnight as the main
issue will once again be the potential for dense fog and low
stratus. At KCHS: conditions currently sit at low MVFR, but
should steadily lower into the IFR range as nearly all
surrounding observations sites are already there. The chance for
fog will then depend on how the sea fog across the Georgia
coastal waters expands and moves inland. The forecast features
most of the fog after midnight and much like last night, once it
settles in we will likely stay in the LIFR range through
sunrise. Conditions in the morning should be quicker to improve
as southwest flow increases and helps to mix out the
fog/stratus. Expect VFR to prevail from the mid/late morning
hours onward.
At KSAV: Dense sea fog quickly developed over the Georgia
coastal waters this evening and pushed onshore in the easterly
flow. The rolling bank of sea fog reached the terminal around
00z and should persist for a few hours. Conditions may bounce
around a little bit through the evening before going solidly IFR
and then LIFR for the remained of the overnight. Fog/stratus
will then improve by mid morning as southwest flow increases and
the low levels begin to mix. Expect VFR to prevail thereafter.
Extended Aviation Outlook: Low clouds or fog could affect either
terminal Tuesday night. Brief flight restrictions possible
Thursday night into Friday with showers along a cold front.
A large low pressure system is expected to bring showers and
thunderstorms across the region Sunday through Sunday night.
&&
.MARINE...
Tonight: Recent calls to the Tybee Island Coast Guard and
Savannah Pilot Office dispatch, combined with satellite imagery
and photos from 41008 reveal that dense sea fog has developed
across the Georgia waters out to about 40 nm offshore. A dense
fog advisory has been issued for all of the Georgia waters and
the southern South Carolina waters through sunrise. The fog is
then forecast to spread across the remainder of the South
Carolina waters and the Charleston Harbor after midnight as the
low level flow weakens and begins to veer to more southerly.
The dense fog advisory may need to be expanded later tonight. Otherwise,
stable conditions will persist in the marine layer. Seas will
be no higher than 1-3 ft.
Fairly quiet marine conditions expected with regard to winds/seas
through Friday as a series of weak fronts affect the waters.
However, sea fog may persist through Wednesday afternoon as weak
onshore flow maintains moist air over the cool shelf waters.
Marine Dense Fog Advisories are possible at times, especially
late afternoon through mid-morning hours.
&&
.CLIMATE...
Record highs for Tuesday, 17 January:
KCHS: 78/2013 and previous years
KCXM: 78/1928
KSAV: 81/1943
Record highs for Wednesday, 18 January:
KCHS: 77/1952
KCXM: 79/1928
KSAV: 81/1937
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Dense Fog Advisory until 8 AM EST Tuesday for AMZ352-354-374.
&&
$$
NEAR TERM...BSH
SHORT TERM...JRL
LONG TERM...
AVIATION...BSH/JRL
MARINE...BSH/JRL
CLIMATE...
Area Forecast Discussion...UPDATED
National Weather Service Corpus Christi TX
850 PM CST Mon Jan 16 2017
.DISCUSSION...
Just made some very minor changes to the dew point and wind grids
for the first period. Otherwise, GFE Forecast Monitor shows nearly
all green fields (winds are a bit high) but hopefully update with
combination of forecast, GFSLAMP and RUC will help lower the
differences which were not big anyway (it just did). PFM and AFM
have been updated. An update to the ZFP is not needed at this
time. Marine forecast looks good at this time as well. Still a
small chance for possible showers along the boundary overnight.
&&
.PREVIOUS DISCUSSION... /Issued 539 PM CST Mon Jan 16 2017/
DISCUSSION...
See Aviation Discussion for 0Z TAFS.
AVIATION...
Front will slowly creep southward on Tuesday, which will provide
the main focus for thunderstorms on Tuesday afternoon. Before 18Z
do not expect much in convection although there could be a few
weak showers near KLRD toward 12Z with weak upslope flow. AOA
18Z...do have TEMPO or PROB30 for all sites, as could have some
wind gusts 30 knots or more and feel relatively confident (given
model data) that thunder will be around. See the four terminal
forecasts for more information.
Before that, as usual we will see lowering of winds/CIGS and in
some locations (KALI and KVCT) VSBYS starting mainly AOB 06Z and
continuing through about 16Z. With rich moisture and low winds due
to proximity of front, will probably develop IFR/LIFR conditions
east of KLRD terminal before 12Z. Winds on Tuesday mainly SE to
start (weak in KLRD), then backing more toward the east during the
day as the front approaches.
PREVIOUS DISCUSSION... /Issued 358 PM CST Mon Jan 16 2017/
SHORT TERM (Tonight through Tuesday Night)...
Weak boundary/front is analyzed to be draped from just west of
Beeville to just west of Orange Grove...to just east of
Alive...extending southward to just west of Kingsville /also
currently evident on WSR 88d 0.5 reflectivity/. Much of short
term forecast is strongly dependent upon placement of front
through the period. Guidance is struggling with its
handling/placement of the boundary and thus forecast certainty is
lower than normal with this forecast package.
Front/boundary is prog to push west this evening...but is
currently farther east than any guidance indicates. As such...I
am hesitant to forecast the front going overly far to the west.
Regardless...the front should at least push west some tonight
which will result in SSE low level flow persisting across the
eastern half of the CWA. H85 moisture levels /which have been
decreasing this afternoon/ are prog to increase again tonight
which may become sufficient for showers to develop in isolated
convergence bands within the low level flow/. Accounting for
such...I have included 20 POPs for the N Coastal Bend and Victoria
area for late tonight. By late in the night...a H5 vort max is
prog to advect towards the area...a 90 to 100 kt h25 jet is prog
to shift farther to the east...and moisture depth is prog to
increase. Combination of these factors /especially the increase in
large scale lift/ should result in a few showers or even an
isolated thunderstorm developing by late in the night across the
NW Brush Country where boundary is currently expected to push
westward towards.
Boundary is prog to slowly push back south and east across the CWA
during the day Tuesday with scattered showers and a few
thunderstorms developing as a result. Again...placement of the
boundary will be critical regarding placement of highest POPs. For
now...I have highest POPs across the N and W CWA for the morning
with chances expanding elsewhere through the afternoon. If
boundary shifts far enough N and W tonight...then much of the
Coastal Plains may remain dry for much of Tuesday.
By late Tuesday afternoon /and especially into the evening
hours/...thermodynamics are prog to become more favorable for
thunderstorm development. Bulk shear values are prog to increase
to roughly 30 to 40 kts...with guidance indicating a marginally
to moderately unstable airmass in place...while upper level
divergence is prog to increase significantly across S TX Wed
evening as a 130kt H25 jet streaks NE across Del Rio and a 100kt
streak shoots across BRO`s CWA. Combination of all these
factors...along with a continued unseasonably high moisture depth
/PWATs prog to be around 1.60"...which is roughly +2 sigma for
mid January/. Result should be the development of scattered to
numerous showers and thunderstorms during the evening. Given the
aforementioned synoptic and thermodynamic features in play...a few
thunderstorms may become strong to severe /especially across the
Coastal Plains where moisture depth and instability are prog to be
the greatest/. A few damaging wind gusts will be possible with
the strongest activity...but with hodographs prog to become
increasingly curved across the Coastal Plains...an isolated
tornado will also be possible. Isolated flooding may also occur
with any cells that begin to train overnight /greatest chances for
isolated flooding currently appear to be across the Victoria
area/...but the overall flooding threat for S TX is currently
expected to be low.
Min temps will continue to be unseasonably warm tonight with max
temps on Tuesday strongly contingent upon amount of precip and
and placement of boundary. Cooler conditions expected by late
Tuesday night as boundary pushes through and rain cooled air
settles in.
LONG TERM...(Wednesday through Monday)...
Frontal boundary will remain draped across the Coastal Bend into
Wednesday. Deep moisture will be located along and ahead of the
boundary with PW values about 1.5 inches. As a result, decent
chances of showers and thunderstorms will continue on Wednesday with
favored locations across from the Brush Country into the Coastal
Bend. Both the GFS and European bring the upper low into the
Panhandle of Texas Wednesday night into Thursday morning, with
trough extending back to the southwest into Mexico. Increased lift
from the trough and upper jet to the north will result in another
round of convection Wednesday night into Thursday. Trough axis will
finally push through South Texas by Thurday night, with quickly
diminishing rain chances from west to east.
Progressive pattern will persist through the end of the forecast
period. Another upper level trough will approach and move through he
region on Friday. However, concerns over moisture availability will
preclude mentioning any chances of rain. A potent system will then
move out of the Southwest US on Saturday into Saturday night, with
the corresponding front moving through Saturday night/Sunday
morning. This system will have the potential to bring some much
stronger winds to South Texas for Sunday.
Temperatures on Wednesday will be tricky depending on evolution
frontal boundary, but 60s across the west and low 70s near the coast
seem reasonable. Then a warming trend will commence Thursday
through Saturday with above normal temperatures (70s and low 80s)
across the region. Only a slight setback in temps are expected
behind the pacific front on Sunday.
&&
.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi 69 78 63 73 58 / 10 40 80 50 40
Victoria 66 75 59 70 57 / 30 60 90 70 50
Laredo 64 75 57 67 56 / 20 50 60 20 20
Alice 65 80 61 70 57 / 10 50 80 50 30
Rockport 67 77 63 69 59 / 10 50 80 60 50
Cotulla 62 68 55 65 53 / 30 60 70 30 20
Kingsville 66 81 62 73 58 / 10 40 70 40 40
Navy Corpus 68 76 63 70 59 / 10 40 70 50 50
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
GW/86...SHORT TERM
Area Forecast Discussion
National Weather Service Quad Cities IA IL
937 PM CST Mon Jan 16 2017
.UPDATE...
Issued at 928 PM CST Mon Jan 16 2017
Late evening update to expand Dense Fog Advisory northward across
all but the extreme northwest counties. HRRR visibility probs
have a good handle on current fog coverage and indicate dense fog
expect for periods of showers. For the sake of simplicity, will
expire the entire advisory at 10 am. However, western counties may
improve before then and later shifts can trim as the situation
warrants. Far northwest Illinois counties may have to be added to
the advisory eventually. Showers and isolated thunder expected to
end east of the Mississippi River after midnight. Some areas have
received more than an inch of rain, and will continue to monitor
some rising tributaries overnight.
UPDATE Issued at 443 PM CST Mon Jan 16 2017
Following collaboration with neighboring offices, have issued a
Dense Fog Advisory for areas along and south of Interstate 80
through midnight. There is some potential for the dense fog to
spread north of I-80 and persist past midnight, so later
adjustments to the headlines may be needed.
&&
.SYNOPSIS...
Issued at 334 PM CST Mon Jan 16 2017
Area radars showed an arching band of mainly rain out ahead of a
nearly stacked surface and sharp upper level low near Kansas City. A
pronounced dry slot was evident behind this band on satellite water
vapor imagery over central MO into south central IA with a trailing
line of showers and scattered thunderstorms from near Quincy south
across MO and AR. Under this dry slot and along and ahead of surface
warm front, dense fog with visibilities below a quarter mile was
reported across northern MO into central IL. Temperatures over the
local area have risen above freezing across the entire forecast area
today, ranging from 33 along the highway 20 corridor to near 40 in
far northeast MO. The surface and upper level low are expected to
continue northeast and gradually weaken tonight, bringing a high
likelihood of dense fog and continued light precipitation overnight
across the forecast area.
&&
.SHORT TERM...(This Evening through Tuesday)
ISSUED AT 334 PM CST Mon Jan 16 2017
Main challenges center around rain chances and the potential for
dense fog overnight as the surface low tracks across southern IA
into southern Lake MI overnight. Have included widespread fog in the
forecast for now as winds go calm in the deep, saturated airmass
over the cold surface. Anticipate there will likely need to be dense
fog advisories over much of the area this evening, then primarily
east of the MS river early Tuesday morning before drier air starts
to wrap in behind the system. Enhanced lift ahead of the upper low,
correlated with lightning observed over northeast MO will spread
into the south and southeast, mainly our west central IL counties
and will keep a mention of thunderstorms this evening. Temperatures
through the night are progged to stay close to the freezing mark in
the far northwest, where readings have not budged much so far today.
Additional precipitation should be light in this area, and with near
saturated air advecting in the potential for any ice accumulation
looks very low. Elsewhere, the heaviest QPF for this system is
currently occurring with the band of rain and additional amounts
overnight are likely to be less than a quarter of an inch. Higher
rainfall rates with thunderstorms early on in the south could lead
to minor ponding issues due to the frozen soils.
Tuesday, the system exits into lower MI with an increasing pressure
gradient and influx of drier and only slightly cool air in the lower
levels to sweep out the early morning fog. However, clouds will
likely hang on in the cyclonic flow, limiting highs to the mid and
upper 30s.
.LONG TERM...(Tuesday Night through Monday)
ISSUED AT 334 PM CST Mon Jan 16 2017
Tuesday night and Wednesday...Spring-like pattern still being
advertised for the coming week and weekend by the latest medium range
model solutions. A passing bout of sfc ridging, under northeastern
flank of broader upper ridge off western CONUS Rex Block, will make
for clearing and cooler conditions later Tue night into Wed morning.
Fcst lows in the mid to upper 20s may have to be adjusted cooler in
some locations. The upper low portion of the western CONUS rex block
will edge eastward acrs the southwestern plains through Wed night
and open along the way. Lee side southerly return flow to begin some
moisture transport up off the western Gulf and toward the MO
Bootheel by Thu morning. Before then, southerly sfc flow and at
least partial sunshine to make for a seasonably mild day Wed, with
mixing depth and large building inversion aloft limiting the warm up
potential. For now will go with low to mid 40s north of I80, to the
mid and upper 40s south. But could see some sites in the south
approach 50.
Thursday and Friday...Both the 12z GFS and ECMWF agree that a
portion of the upper low in upstream block to roll northeastward and
interact with some me of the moisture return to produce mainly
showers or areas of rain into portions of the area late Thu and into
Fri morning. In areas of convergent light east to southeasterly
flow, could also have some fog issues Fri morning. Fri highs still
well up in the 40s despite clouds and boundary layer saturation. If
the more organized areas of rain hold off or stay to the east and
west, fog, drizzle and low clouds may be the story fro Fri night.
Saturday through next Monday...The latest run medium range solutions
suggest the next main upper wave in the southern stream of the
western into central CONUS blocking complex, will roll out toward
the western OH RVR and TN Valleys through Sunday night. Besides a
lull period for a portion of Sat allowing for another unseasonably
mild day with highs in the upper 40s to lower 50s in much of the
local fcst area, this upper level feature with a trowal like wrap-
around moisture source may make for a rather wet second half of the
weekend and into Mon if the current low center advertised by the 12z
runs verifies. The 12z GFS would have seasonably heavy rainfall of a
half inch to around an inch hitting the southern half to third of
the CWA, while the ECMWF if further south with it`s heavier rainfall
wrap-around hitting MO and southern IL on northern flank of the
vortex. With cold air bottled up acrs Canada, the weekend system
look to be mainly rain, but will have to watch for some northerly
draw on the northwest flank of the large passing cut-off low late
Mon into Monday night that may eventually produce some precip type
issues especially in the western and northern portions of the CWA.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
ISSUED AT 539 PM CST Mon Jan 16 2017
Widespread LIFR to VLIFR conditions will be common at all TAF
sites overnight with dense fog, drizzle and low stratus. There
will likely be a 2 to 3 hour window of showers and perhaps a
rumble of thunder prior to midnight, most favored at KMLI/KBRL.
Visibilities will improve somewhat during the rain. Drier W/NW
winds behind the exiting surface low will provide some improvement
between 08z-13z.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Dense Fog Advisory until 10 AM CST Tuesday for Benton-Buchanan-
Cedar-Clinton-Delaware-Des Moines-Dubuque-Henry IA-Iowa-
Jackson-Jefferson-Johnson-Jones-Keokuk-Lee-Linn-Louisa-
Muscatine-Scott-Van Buren-Washington.
IL...Dense Fog Advisory until 10 AM CST Tuesday for Bureau-Hancock-
Henderson-Henry IL-McDonough-Mercer-Putnam-Rock Island-
Warren-Whiteside.
MO...Dense Fog Advisory until midnight CST tonight for Clark-Scotland.
&&
$$
UPDATE...RP Kinney
SYNOPSIS...Sheets
SHORT TERM...Sheets
LONG TERM...12
AVIATION...RP Kinney
Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
938 PM CST Mon Jan 16 2017
.UPDATE...
Made few minor changes to the first period. Removed mentioning of
isolated thunderstorms across the eastern part of South Central Texas
through at least midnight tonight. The new NAM12 and HRRR model
solutions keep light showery activity across the eastern half of the
area through the overnight hours. Later tonight, the warm front is
expected to push back to the north and to the east of the I-35
corridor. Area forecast soundings suggest a light chance for elevated
convection and decided to go with isolated thunderstorms across the
far east after 06Z Tuesday. Showers and thunderstorms are expected to
increase late Tuesday morning into the afternoon as the warm frontal
boundary interacts with the upper level forcing of an upper level
disturbance over the four corners region moves into Southern Plains.
A few isolated strong to severe storms are possible Tuesday afternoon
across the far southeast where instability values and forcing are
best.
&&
.PREV DISCUSSION... /ISSUED 556 PM CST Mon Jan 16 2017/
AVIATION.../00Z TAF CYCLE/
VFR conditions are ongoing as of 2355Z at terminals but decreasing
ceilings through the next 1-2 hours will create MVFR conditions
through the early to mid-evening hours for KAUS/KSAT/KSSF. Further
reduction to IFR is expected after 06Z for those respective sites as
a cold front shifts back west towards the I-35 corridor. In addition
to the low ceilings, -SHRA is on going across the Texas Coastal
Plains and this activity will shift west into the KAUS/KSAT/KSSF
terminals overnight and remain through a good portion of Tuesday.
Have placed VCSH and -DZ. -RA may need to be added based on trends
overnight. Visibilities will also likely drop overnight as the front
backs up as a weak warm front. Visibilities could drop down to 3-5SM
and could be lower at times through the day Tuesday with saturated
and -SHRA conditions. KDRT will be delayed in MVFR and IFR until
09-11Z Tuesday morning but will eventually follow suit as other TAF
sites. Little recovery is expected Tuesday as the stalled front
remains over the area. IFR then MVFR by the afternoon will hold on
most of the day.
PREV DISCUSSION... /ISSUED 311 PM CST Mon Jan 16 2017/
SHORT TERM (Tonight through Tuesday Night)...
Late afternoon surface observations show a weak cold front in place
from just north of Giddings to just north of Pleasanton. East of this
boundary, isolated to scattered showers continue to move from south
to north across the coastal plains and Highway 77 corridor. Most
hourly rainfall totals are around one quarter inch or less. However,
a few spots have picked up close to three quarters of an inch in an
hour with repeated showers moving over the same area.
For tonight, the frontal boundary will gradually slide southward as a
reinforcing surge of surface high pressure moves in from the north.
This should keep the higher rain chances east of the I-35/I-37
corridors tonight. We do expect an increase in warm air advection
just above the surface front to take shape tonight. This will lead to
low clouds spreading north and westward across south central Texas,
with cloudy skies across all areas by Tuesday morning. The warm air
advection pattern strengthens on Tuesday as an upper level low
pressure system approaches from the west. This will lead to
widespread showers along with a few thunderstorms on Tuesday. Highs
will also be cooler with lower 50s in the Hill Country to lower 60s
in the coastal plains. For late Tuesday afternoon and evening, we
can`t completely rule out a strong storm or two across the coastal
plains with a lingering frontal boundary and some lift associated
with the upper level trough. Areas of concern include Karnes, DeWitt
and Lavaca counties. In addition, we could see some locally heavy
rainfall given into Tuesday night given training of cells within a
moist (precipitable water values ~ 1.5") environment. At this time,
we will not mention heavy rain in the forecast or Hazardous Weather
Outlook as the above mentioned areas have not seen any significant
rains recently.
LONG TERM (Wednesday through Monday)...
Rain chances continue to remain high across most of south central
Texas on Wednesday as an upper level trough axis continues to
organize to our west. This trough does begin to move east across
Texas Wednesday night and Thursday and we will show decreasing rain
chances from west to east. A much drier weather pattern will take
shape for the end of the work week into the upcoming weekend as the
quality low-level moisture should remain east of the region. We do
expect another upper level trough to move through on Sunday, but
given the lack of moisture, we will only keep a low chance of
rainfall across the coastal plains and Highway 77 corridor on Friday
and Saturday. Sunday is shaping up to be quite windy across the
region as a band of stronger mid-level winds is forecast to move
across central Texas. We have increased wind speeds and will need to
monitor in subsequent forecasts.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 62 56 48 61 49 / 30 60 70 60 20
Austin Bergstrom Intl Airport 60 57 48 61 49 / 30 60 70 70 20
New Braunfels Muni Airport 64 57 49 62 50 / 30 60 70 60 20
Burnet Muni Airport 61 53 45 58 46 / 20 60 70 50 10
Del Rio Intl Airport 63 59 49 65 47 / - 60 50 10 10
Georgetown Muni Airport 64 54 46 59 47 / 20 60 70 60 20
Hondo Muni Airport 66 60 50 65 49 / 20 60 70 50 10
San Marcos Muni Airport 61 57 49 62 50 / 30 60 70 60 20
La Grange - Fayette Regional 60 61 52 63 53 / 50 60 80 70 50
San Antonio Intl Airport 64 59 50 63 51 / 30 60 70 60 20
Stinson Muni Airport 66 60 51 63 51 / 30 60 70 60 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Mesoscale/Aviation...Allen
Synoptic/Grids...17
Public Service/Data Collection...30
Area Forecast Discussion
National Weather Service Goodland KS
504 PM MST Mon Jan 16 2017
.UPDATE...
Issued at 500 PM MST Mon Jan 16 2017
With precipitation having ended across the forecast area and no
further precipitation expected overnight, have cancelled the
winter weather highlights across the forecast area. With
temperatures in the lower to mid 30s across the forecast area
today, much melting has occurred, which has helped most major
roadways to become clear with only areas of either wet or icy
conditions remaining. Expect some refreezing overnight as
temperatures drop into the lower 20s and teens, but do not expect
any additional precipitation from this point on as the storm
system continues to move away from the central high plains region
and towards the upper midwest.
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 135 PM MST Mon Jan 16 2017
H5 low continues to move off to the northeast this afternoon. Snow
transition was a bit slower than expected thus ice amounts were
higher and snowfall totals lower. Much of the CWA is transitioned to
snow where precipitation is falling with occasional reports of mixed
sleet and freezing rain. A persistent but weak band of snow
stretches from Hitchcock county in Nebraska to central Kit Carson
county in Colorado. This band is very slowly moving to the east and
areas within this band of light snow could pick up an additional
inch of snow. HRRR mesoscale and SREF plumes indicate that most
areas will see precipitation chances quickly diminish as the
afternoon progresses, ending by around 00Z. Temperatures will hover
in the lower 30s for the most part with upper 20s in the
northwestern portions of the CWA. Skies will clear tonight from
northwest to southeast.
Mostly clear skies will prevail Tuesday with a rebound in
temperatures. Highs will reach the upper 30s to middle 40s across
the CWA.
.LONG TERM...(Tuesday night through Monday)
Issued at 121 PM MST Mon Jan 16 2017
For the extended period...latest GFS/ECMWF models have been trending
the past several runs with zonal H5 flow across the northern half
of the country...with a cutoff low setting up over south central
portions of the country. This upper level system makes a slow push
northward towards the Central Plains by Friday...lifting across
the Central Plains Friday night...followed by another quick moving
system that pinwheels into the region off the Central Rockies for
the upcoming weekend.
With the cutoff system anchored over south central portions of the
country for the first half of the extended...surface high pressure
mainly east...with troughing over the front range. This will give
the area near to above normal highs Wednesday into Friday...before
trending colder as the approach of the two aforementioned systems
will bring increased cloud cover with the chance for precip.
Looking for daytime highs to reach the 40s with a trend lower into
the upcoming weekend. Depending on the speed of these two
systems...highs could be affected by several degrees due to the
strength of the CAA on the wrap-around/exiting side of each low.
Overnight lows will range in the 20s.
For precip...limited qpf at present to keep pops in chance category
for now...but speed of each system thru the area combined with some
upslope effects on the easterly/southeasterly flow could give the
area enhanced precip especially at night in terms of -sw based on
expected temps. Warm enough during the day for -rw.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 424 PM MST Mon Jan 16 2017
VFR conditions are expected at MCK and GLD through the TAF
period as the low pressure system that brought ice and snow to the
plains continues to move into the upper midwest.
Northwest winds will become light early this evening as low to
mid level clouds continue to decrease through the overnight
hours. A few high clouds will remain during the morning to be
followed by clear skies and light winds out of the southwest by
late Tuesday afternoon.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...LOCKHART
SHORT TERM...TL
LONG TERM...JN
AVIATION...LOCKHART
Area Forecast Discussion...UPDATED
National Weather Service Huntsville AL
722 PM CST Mon Jan 16 2017
.NEAR TERM...(Tonight)
Issued at 648 PM CST Mon Jan 16 2017
Latest surface analysis shows a high centered along the Mid Atlantic
Region with a low centered near Kansas City, Missouri. A trailing
cold front from the surface low extended southward through the
Arklatex into Deep South Texas. Closer to home another warm winter
evening with temperatures currently running in the lower to middle
60s under mostly cloudy skies.
Regional radars show a rather expansive shield of showers and a few
thunderstorms extending across the Mississippi River Valley. Patchy
shower activity was noted further east from middle Tennessee across
the Shoals and into central MS. The latest HRRR and high res WRF both
indicate a s/w trough approaching from the west this evening. This
coupled with some enhancement with the nocturnal jet should help to
increase rainfall potential overnight and spread the precipitation
shield further east.
Overall, the current forecast is pretty good shape. May make some
minor tweaks to the PoP/QPF grids slightly for higher values in the
far western areas. Have already made very minor adjustments to hourly
temps as well.
.SHORT TERM...(Tuesday through Wednesday)
Issued at 132 PM CST Mon Jan 16 2017
The cold front will be right on our doorstep by daybreak on Tuesday
and then slowly move eastward through the day. By this time, the
upper level trough will weaken and become situated over the eastern
Great Lakes, with mid and upper level flow becoming nearly zonal.
There may not be much progression as it becomes oriented east to
west and parallel to the flow aloft. An abundance of moisture will
remain in place as this front moves eastward the area, thus precip
chances were kept around 60 to 70 percent through the day. As stated
above, most of the forcing will be well removed from the area,
however did keep isolated thunder in the forecast, as forecast temps
rise into the 70s and allow for some weak instability.
The front will slowly shift to the south during the overnight hours
on Tuesday, with the higher precip chances coming to an end. Kept in
slight chance to chance pops, given some uncertainty with how far
south the front will reach before it stalls. However, guidance is in
fair agreement that it will stall south of the area, giving us a
break in the rainfall on Wednesday. In addition, winds will shift to
the north behind the front, and weak CAA will bring slight cooler air
into the TN Valley. Forecast high temperatures are expected to remain
in the lower 60s on Wednesday.
.LONG TERM...(Wednesday night through Sunday)
Issued at 250 PM CST Mon Jan 16 2017
Good agreement with this frontal positions in model data, so
confidence is fairly high that the ridge will finally break
down towards the middle/end of the week and rain chances will
increase. Although the ridge looks to build back in briefly during
the day on Wednesday over the Tennessee Valley, a potent upper low
develops upstream Wednesday night into Thursday morning over
the Texas/Oklahoma area.
During this time, increasing southerly flow and fairly strong
shortwaves could produce some heavier showers Wednesday night. At
this point instability looks too meager for any thunderstorms, but
wouldn`t be shocked to hear a rumble of thunder. Rain chances look
to increase from chance to likely by Thursday morning across
northern Alabama. Isolated thunderstorms are possible, as some
elevated instability develops. At this point, they do not look very
strong though.
Through the day on Thursday, models continue to show weaker
disturbances continuing to push northeast ahead of the main upper
low, which moves little through much of Thursday. This could help to
keep instability a bit lower due to shower/storm activity/cloud
cover. However, isolated thunderstorms will remain possible.
By late in the day on Thursday, models converge on this upper low
finally kicking northeastward into Missouri and Kansas. A very
strong shortwave develops on the southeast portion of this upper low
and rotates northeastward through the Tennessee Valley Thursday
night. Although there is some potential for instability to be cut-
off to our southwest on Wednesday, do not think given the track of
the upper low/associated shortwave that this will happen with this
system. Trends are not moving this upper low more east or southeast.
Surface CAPE is not great, but could reach 300 J/KG in northern
Alabama/southern middle Tennessee. A little better elevated CAPE is
forecast (around 600 J/KG). Extremely strong upper level
forcing/vorticity is progged by all models with this system. This
strong forcing couples with a 40 kt 850 mb jet, ample moisture, and
a 60 kt 500 mb jet. Based on parameters and synoptics, a potential
for strong to severe thunderstorms continues to be a possibility on
Thursday night into Friday morning. However, believe surface based
instability is too meager for tornado development. Damaging winds
and small hail look like a decent possibility given other
ingredients. In addition, PWATS due to strengthening southerly flow
will increase to around 1.4 inches by Thursday afternoon into
Thursday night. This will allow for heavier rainfall totals with
this system, possibly between 1 and 2 inches with locally higher
amounts. Rainfall amounts may be higher given such strong forcing.
I would not be surprised to see a record high minimum temperature or
two on Friday morning (given strong southerly flow), but did not go
quite that warm at this point.
Models are fairly convergent moving this energy quickly north Friday
morning. By 10 am, we might only be cloudy with a bit of very light
rain primarily east of I-65. Models are hinting at a brief break
from cloud cover Friday morning. This might allow us to climb back
into the upper 60s or a bit higher again.
As an even stronger system moves from Oklahoma into Arkansas on
Saturday night into Sunday, rain chances increase again. However,
with a front stalled to our southeast, this may keep better moisture
and instability well south of the area through Sunday morning.
However, given again how strong this forcing is forecast to be, by
Sunday afternoon into Sunday evening, another round of strong to
severe storms may be brewing. Instability is higher with this system
by Sunday afternoon/evening, but this is still seven days out.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 515 PM CST Mon Jan 16 2017
A cold front slowly approaching from the west will bring a higher
probability of light rain/rain showers over the next 24 to 36 hours.
Ahead of the frontal boundary, VFR ceilings this evening will slowly
lower to MVFR category overnight. Have also included predominant rain
after midnight though precipitation intensity should be rather light
and visibilities unrestricted for the most part. Ceilings will likely
continue to lower into IFR category late tonight/early Tuesday, as
moisture increases underneath shallow inversion. Conditions will
improve somewhat by Tuesday afternoon with heating of the boundary
layer but MVFR level ceilings look likely. Winds will remain southerly
at 8-11 knots through the period.
&&
.HUN WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
TN...NONE.
&&
$$
NEAR TERM...15
SHORT TERM...73
LONG TERM...KTW
AVIATION...15
For more information please visit our website
at weather.gov/huntsville.
Area Forecast Discussion
National Weather Service Wilmington NC
1057 PM EST Mon Jan 16 2017
.SYNOPSIS...
A warming trend will occur Tuesday and Wednesday ahead of a
cold front which will drop south through the Carolinas late
Wednesday. Cooler and drier high pressure will follow on
Thursday. Low pressure moving up from the Gulf coast will
drag a warm front through the area on Friday. High pressure
will build in on Saturday before another system brings
unsettled weather for Sunday.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 1030 PM Monday...Latest HRRR continues to include patchy
light rain during portions of late this evening into the
overnight period...mainly along and west of the I-95 corridor.
Also, HRRR includes showers over the coastal counties mainly
from Horry County northward, and the adjacent coastal waters.
Once again upped the cloud cover to mostly cloudy or completely
overcast via latest satellite imagery trends and 18Z model
data. Continued with the patchy to areas of fog late this
evening and overnight given latest sfc obs trends and locally
run fog algorithm. The low stratus to affect the ILM CWA
Carolina Coasts and adjacent waters and refrained from
indicating sea fog at this juncture with the difference between
sfc dewpoints and SSTS not large enough. Temps tonight will
either hold steady or drift slightly lower from current values
thru this evening and overnight. Basically, not your normal
diurnal temp curve.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
As of 300 PM Monday...For as weak as the aforementioned near
term warm advection is Tuesday will sure turn out a mild
afternoon. This will be more a function of not being trapped
under a deep and moist inversion. The moisture will not be
completely eroded however as forecast soundings show some
lingering moisture in the 3-5kft layer as well as above about
7500ft. The high level moisture in particular probably lingers
Tuesday night and then low level moistening gets underway
Wednesday compliments of approaching cold front. Timing
differences with respect to the front are affecting
temperature guidance with the slower WRF allowing for an even
warmer afternoon than the quicker GFS. Stayed closer to the
lower values due in part to support from the EC. Any
significant rainfall will stay north of the area underneath the
upper trough though a few sprinkles or stray hundredth of an
inch or three cannot be ruled out locally.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 300 PM Monday...Unsettled remains the operative word
for the extended period courtesy of a highly amplified and
shortwave laden pattern.
The first significant system for the eastern Carolinas arrives
late Thursday into early Friday via a shearing mid level system
moving across the Tennessee and Ohio valleys. A weak occluded
front is paired with this system as is a stationary front to the
south but these have little impact on the sensible weather.
Overall the inherited chance of showers still looks good.
The second more potent system at least to this point arrives late
Sunday into early Monday via a more powerful and closed shortwave
traversing a similar path to the first system. This system
continues to strengthen via the medium range guidance with good
moisture advection from the Gulf of Mexico and Atlantic.
Combined with good difluence aloft the elements for a soaker are
in place. Citing the dynamics, a high shear/low cape convective
event is possible with plenty of details to be determined in
the coming days.
The temperature forecast has shown little change with the latest
guidance and with a moisture laden period (even outside of pops
plenty of cloud cover) there shouldn`t be much diurnal variation.
Expect highs generally in the 60s and lows in the middle to upper
40s with some areas (generally coastal and southern) not dipping
below 50.
&&
.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
As of 00Z...Expect MVFR/IFR conditions this evening to become
IFR/LIFR for the overnight hours as stratus allows for low cigs
to become widespread, with patchy areas of fog as well. Light
northeasterly winds will prevail. On Tuesday, anticipate
deteriorated conditions to continue through midday, with a
gradual improvement to VFR as cigs lift by the late afternoon
hours as winds become west-southwest, around 5 to 10 kts.
Extended Outlook...Cold front Wednesday, accompanied with
showers and MVFR. Showers possible Friday. Otherwise expect
VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
As of 1030 PM Monday...A stalled boundary extending inland in
the vicinity of South Santee River has hooked up with an
inverted sfc trof of low pressure just offshore and parallel to
the Carolina Coasts. The 2 boundaries as a whole will begin
lifting northward overnight into daytime Tuesday. This sfc
pressure pattern and rather relaxed sfc pg will for the most
part produce NE winds at 10 to 15 kt, veering to the ENE to ESE
around 10 kt by daybreak.
Significant seas will run 2 to 3 ft. A degrading ESE 1 to 2
foot ground swell at 9 second periods will combine with locally
produce wind driven waves at 5 to 6 second periods.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 300 PM Monday...With the warm front lifted out to our
north on Tuesday the gradient will remain quite weak. SW flow
will be capped at just 10kt and seas may drop to just 2 ft. The
approach of a cold front will veer and increase the flow
gradually Tuesday night and then moreso Wednesday. This front
may pass through either midday or late afternoon Wednesday. The
cooler surge behind this boundary is tempered enough that no
headlines likely follow its passage.
LONG TERM /THURSDAY THROUGH SATURDAY/...
As of 300 PM Monday...Expect essentially light and variable
winds Thursday via a weak pressure pattern. Wind fields will
show a little better definition late Thursday into Friday as a
southwest flow develops ahead of a weak front. Speeds increase
briefly to 10-15 knots. By Saturday a weak northerly flow
develops. Significant seas will be 2-4 feet as the weak wind
fields and fetch change keep them somewhat in check.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.
&&
$$
SYNOPSIS...SHK
NEAR TERM...DCH
SHORT TERM...MBB
LONG TERM...SHK
AVIATION...SGL
Area Forecast Discussion
National Weather Service Wilmington OH
908 PM EST Mon Jan 16 2017
.SYNOPSIS...
Warm front will continue to push northward this evening. A cold
front will move through on Tuesday. An upper level disturbance
will keep precipitation chances in the forecast Tuesday night
into Wednesday morning.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
The initial wave of isentropically induced showers is lifting
northeast across our area attm. We should then see a brief lull in
the more widespread precipitation for a couple of hours before
the next wave of precipitation moves in. This second wave will be
associated with the combination of some mid level energy and a
strengthening 40-50 knot low level jet. Expect precipitation to
be fairly widespread so will keep the categorical pops going
through the night. We are seeing several lightning strikes
upstream across western Kentucky and Illinois, now pushing into
western Indiana. The instability should weaken some through the
night but given the fairly dynamic system and the fact that some
weak elevated instabilities are progged to overspread our area
through the early morning hours, think a few thunderstorms will
be possible later tonight across our area. Temperatures are
currently running from the lower 40s north to the lower 50s
south but these should gradually rise overnight in the
strengthening southerly low level flow.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
A cold front will move through on Tuesday. There is some weak
instability and therefore have some thunder mention in the
forecast. Although there will be a lull in the precipitation
Tuesday afternoon and early evening a decent upper level
disturbance will bring scattered rain showers to the region
Tuesday night into Wednesday morning. The greatest coverage of the
shower activity will be across northeastern portions of the
region. Some lingering drizzle will be possible on Wednesday
before precipitation tapers off. Even as precipitation tapers off
on Wednesday lots of low level moisture remains and keep clouds
around through the day on Wednesday. High pressure and dry
conditions are expected Wednesday night.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
High amplitude upper air pattern with energetic systems will prevail
through the period. Upper low in the Plains will open up as it
pivots north. This will result in low pressure tracking up the Ohio
Valley and weakening as it heads into the lower Great Lakes early in
the period. Showers will accompany this system Thursday night into
Friday. After this moves by, southerly flow will remain with much
above normal temperatures continuing into the weekend. A large upper
low will track into the mid Mississippi Valley on Sunday and then
turn northeast on Monday bringing more showers to the region. Cannot
rule out a bit of thunder as well.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
The initial band of showers is overspreading the area early this
evening. As this leading band has approached, cigs have actually
gone VFR across much of the area. Will therefore go a bit more
optimistic with the cigs in the early stages of the TAFs but as
the low levels saturate back up, do expect cigs to drop back down
into IFR category later this evening and into tonight. After the
initial band, it looks like we may see a couple hour lull in the
precipitation before the next wave of rain moves in overnight.
This is associated with decent short wave energy and a
strengthening 40-50 knot 925-850 mb low level jet rotating up
across the region. Some marginal elevated instabilities will also
be pulled up into the area later tonight so think a few
thunderstorms are not out of the question. Would expect the best
chance for this to be at the southern TAF sites so will include a
VCTS at KCVG/KLUK for a few hours later tonight. Given the
strengthening jet, low level wind shear will also be possible
overnight but both the NAM and GFS keep bulk shear values just
below 40 knots through the night (although the stronger LLJ on the
RAP does meet criteria at times in the 06Z-12Z time frame). Rain
showers will continue into Tuesday morning until a cold front
pushes east across the area through late morning. Behind the
front, winds will swing around to the west and become a little
gusty through the afternoon.
OUTLOOK...MVFR/IFR ceilings and MVFR visibilities through
Wednesday. MVFR/ IFR ceilings are again possible Thursday
afternoon through Saturday.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...Novak
NEAR TERM...JGL
SHORT TERM...Novak
LONG TERM...
AVIATION...JGL
Area Forecast Discussion
National Weather Service Lincoln IL
849 PM CST Mon Jan 16 2017
.UPDATE...
Issued at 840 PM CST Mon Jan 16 2017
Surface low pressure approaching Quincy early this evening will
continue to track northeast across the northern half of our
forecast area during the remainder of the evening hours. A band
of showers was located right with the surface low and those will
track over the area through the late night hours. Winds will drop
off as the low moves across the area with the areas of dense fog
holding into the early morning hours accompanied by mainly light
rain or drizzle. Temperatures will continue to slowly rise this
evening until the low shifts off to our northeast during the early
morning hours. Winds will turn into the southwest just ahead of
the low and then turn more westerly as it moves away. Despite a
cold frontal passage early Tue morning, short term models suggest
another band of dense fog will follow the cold front in during the
early morning hours through at least late morning. We may have to
extend and even expand the current dense fog advsy thru at least
the mid morning hours on Tuesday. Have made some changes to the
weather grids in adding the fog threat thru Tue. morning and
adjusted some POPs as well late tonight into Tue. We should have
the updated zones out by 915 pm.
&&
.SHORT TERM...(This evening through Tuesday)
ISSUED AT 243 PM CST Mon Jan 16 2017
Will need to extend the dense fog advisory through the rest of the
afternoon from I-72 north while letting it expire at 3 pm south of I-
72. Easterly winds are shifting southeast and advecting the dense
fog into area nw of the IL river. Peoria and Lacon have returned to
dense fog and Galesburgs vsbys is slowly dropping. Visibilites from
Jacksonville, Springfield, Decatur and Paris south have improved to
1-4 miles in past hour. Widespread dense fog caused in part by
mild/moist air moving over a cold ground (6 am frost depth at
Lincoln was 4 inches and 10 inches at Altona). The latest runs of
the HRRR and RAP models showing areas of fog and locally dense fog
lingering over northern CWA into this evening and lasting longest
over the IL river valley. Visibilities should improve during
overnight as a cold front moves east across IL.
20Z/2 pm surface map shows 1010 mb low pressure over east central KS
with a warm front lifting northward into central parts of MO and KY
and southern IL south approaching I-64. Bands of rain showers were
over IL with a few thunderstorms over eastern MO and lifting ne
toward the MS river. Temps currently range from mid 30s from Macomb
to Lacon northward to the lower 50s south of I-70.
Models deepen surface low pressure from east central KS northeast to
southern Lake MI by 12Z/6 am Tue with pressure down to 1007 mb. A
warm front will lift northward over central IL (especially se of the
IL river) during this evening, followed by the cold front sweeping
eastward across IL during overnight. Have likely to categorical
chances of showers along with isolated thunderstorms this evening,
then gradually diminish pops behind the cold front overnight with
highest pops in eastern IL where isolated thunderstorms still
possible til 3 or 4 am when cold front reaches near the IL/IN
border. Isolated light rain showers could linger over eastern IL and
areas from I-74 ne on Tue morning. Rainfall amounts through tonight
to range from 0.40-0.75 inches. Lows early Tue morning range from
upper 30s nw of the IL river to the lower 50s near the Wabash river
and these will also be the highs early Tue morning. Temps nearly
steady or slowly slipping during the day with WSW breezes.
.LONG TERM...(Tuesday night through Monday)
ISSUED AT 243 PM CST Mon Jan 16 2017
Models are in very good agreement that the modified southwest flow
will continue across the region through the week. Surface high
pressure will build into the area from the west as this past
weekends weather system finally moves off to the east. This high
pressure will keep mild conditions over the area with dry weather.
This will be a brief period of dry weather as another weather system
develops in the southern plains and lifts northeast, in the
southwest flow, through the Miss valley and eventually into the Ohio
valley. Models differ on the intensity of this system, but all agree
that the main low pressure area associated with the system will
remain southeast of the area through the period. The chance of
precip will run from Thursday in the southeast through Friday
morning. The best chance of pops will be in the southeast on
Thursday night. Despite being northwest of the track of the low,
temps overall will remain mild so all precip will be liquid and not
expecting any snow or freezing precip.
Another brief dry period is expected Friday night through Saturday
as the CWA will be in the warm sector ahead of the next weather
system expected for the latter part of the weekend. Models have some
differences with how and where this system first evolves, but agree
that the main low pressure area will come out of the southern plains
and lift northeast somewhere across the mid Miss valley. Location of
this track is where the models struggle with any agreement, but do
agree on the intensity of the system. Precip will move into the area
Sat night and then spread across the CWA for Sun and Sun night.
Temps will remain mild with this system and early look suggests it
will be quite windy as well.
Overall temps will remain warm/mild through the forecast period
with the warmest temps being Sat and Sat night.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 452 PM CST Mon Jan 16 2017
LIFR with occasional VLIFR conditions in fog will continue
through the evening hours with only a gradual improvement
after 02z as the warm front lifts across the area. However,
as the cold front associated with the storm system to our
west shifts across the area after 05z, we will see a return
to the dense fog and low clouds behind the front. We really
won`t see much of any long term improvement until after 16z
Tuesday as somewhat drier air advects in from the west and
northwest. Surface winds will be southeast this evening
with speeds 10 to 15 kts and then become southwest to west
in the 04z-08z time frame with similar speeds overnight.
West winds are expected during the day Tuesday at 10 to 15
kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until midnight CST tonight for ILZ027>031-
036>038-040>050.
&&
$$
UPDATE...Smith
SHORT TERM...07
LONG TERM...Auten
AVIATION...Smith
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
904 PM CST Mon Jan 16 2017
.UPDATE...
904 PM CST
Evening Update:
Little change to going forecast this evening, with the exception
of the earlier expansion of the dense fog advisory and extension
in time through midnight. While visibility has improved with rain
in some spots, will likely have to consider extending dense fog
advisory farther north and past midnight.
Current round of moderate rain/showers and embedded thunder has
helped to mix out fog in spots and raise visibilities, though with
trailing edge of more widespread rain moving out over Lake
Michigan and off into Indiana over the next couple of hours would
expect fog to redevelop and thicken. Some evidence of this is
noted across western Illinois where visibility has lowered back
into the 1/4-3/4SM range in spots. Based on this thinking am
planning on letting the current advisory continue, and will
monitor fog/vis trends for possible extension overnight and
northward expansion across remainder of northern IL. Dense fog
will probably become especially likely toward morning as gradient
weakens with approach of surface low.
Another area of rain moving into western IL (which will also
likely modulate fog/low vis trends) is associated with the mid-
level trough and vorticity center, and this is expected to lift
across the area after midnight after a lull in organized precip.
Would expect light rain/drizzle to persist within this lull region
so trying not to get too detailed with hourly pop/wx grids.
Lightning detection network has been indicating isolated thunder
continues to occur across the I-55 and I-57 corridors with
initial band of elevated convection, where RAP mesoanalysis
initializes 100-300 J/kg of MUCAPE available roughly within 850 mb
thete-E axis. Guidance has been consistent in redeveloping this
axis back northward again in advance of the main vort, so have
kept a slight chance of thunder in overnight.
Overall, going forecast has this pretty well in hand and only
further changes will be to consider expansion of fog headlines
during the late evening hours.
Ratzer
&&
.SHORT TERM...
235 PM CST
Through Tonight...
The low over the Kansas/Missouri border will move over northern IL
late tonight/early Tuesday morning. Soggy conditions will continue
through that time. The good news is temperatures will remain above
freezing through tonight so no additional freezing rain or ice is
expected. Rain continues through the night with periods of moderate
rain possible. An additional 0.5 to 1.0 inch of rain is expected
through tonight with higher totals north of I-80. Forecast soundings
also feature a little elevated instability so a few isolated,
embedded thunderstorms are possible this evening. While an isolated
storm may occur anywhere across the forecast area, the best chance
is along and south of I-80. Convection/thunderstorms may result in
locally higher rainfall amounts.
Dense fog will likely continue south of the current rainfall
(Livingston and Kankakee counties south and all of northwest
Indiana) through this afternoon when steadier rain arrives. I have
medium confidence in how dense fog will be tonight. The abundance
of moisture will likely result in around 1 to 2 mile visibility, but
periods of drizzle may bring visibilities down to less than a mile.
Decided to go with widespread fog, but no mention of dense fog
tonight due to low confidence.
JEE
&&
.LONG TERM...
235 PM CST
Tuesday through Monday...
High impact weather chances are presently low in the extended
with a pattern atypical for January. Precipitation type looks to
remain mainly if not entirely rain during the latter part of the
week and weekend. While certainly an above normal temperature
pattern for January will strengthen, do have concerns on how far
above normal, especially near the lake front where they could be a
stiff onshore component at times, or much of, later this week and
through next weekend.
The surface low by Tuesday morning is expected to be in southwest
Michigan with gradually increasing northwest surface flow. Early
morning fog, some of it possibly dense, should ease from west to
east across the area. Scattered early morning showers also should
depart east with this system, but clouds will stick around with
high confidence. Temperatures will likely be well into the 40s
across northwest Indiana at daybreak, but as the system warm
sector moves east, temperatures there will cool, and elsewhere
likely hold steady.
A northern stream upper short wave disturbance will move east into
Wisconsin tomorrow afternoon and likely tap some of the moisture
left in the wake of the preceding, deeper system. Convective
allowing guidance with solutions that far do indicate isolated to
scattered showers across Wisconsin and northern Illinois during
the late afternoon shifting southeast into the early evening. Have
nudged up pops a tad during that time frame. The column will be
cooling, with a small chance for some brief wet snow before
showers end.
With fairly quick height rises late Tuesday night into early
Wednesday, a scattering of the persistent clouds is expected.
Temperatures will gradually moderate on southwest to south winds
Wednesday and then Thursday, with 40s for highs likely areawide.
A large blocking upper ridge across eastern NOAM, with heights
near record across eastern Canada, will keep systems from an
active Pacific jet slowing as they move into the middle of the
country. Not only will they slow, they look likely to occlude,
keeping precipitation influence potentially minimal over our area,
or at least slowing chances. Do have the chances for rain lifting
north late Thursday night and Friday with a first system. Have
higher chances with the next system predicted by 12Z global models
to move into the Ohio River Valley one week from now. Confidence
in this system and timing is very low.
The forecast 925mb temperatures are well above normal, especially
by Friday into the weekend. Given the multiple systems over the
plains, at the surface an east wind is presently forecast, and at
times fairly stiffly. Given water temperatures in the lower 30s,
lake adjacent counties including downtown Chicago would remain
quite a bit cooler than inland locations that have a good
potential for low 50s one or both days this weekend.
MTF
&&
.AVIATION...
For the 00Z TAFs...
IFR/LIFR conditions in ra will be the primary concern for the
night and into tomorrow morning. However, there is still a small
chance for isold TS to impact the terminals this evening.
Low pressure has moved over nrn MO and will continue to track
northeast through the night. Expect that cigs/vis will continue to
drop as the low approaches and a warm front...initially over cntrl
il/in moves north through the area. As the low approaches nrn IL,
the warm front will lift to the north of the terminals, allowing
winds to veer to more ely-sely. An upper level disturbance is
generating some isold TS, so will keep the short tempo TS in the
TAFS, but latest timing suggests that the window of opportunity
for TS invof the terminals will be a little earlier than
previously timed. Cigs across the region are settling to arnd
200-300ft and and vis should drop to below 1sm across the area,
with prevailing 1/2 to 3/4sm likely. A few isold spots may drop to
1/4sm, but will not introduce such low vis to the TAFs at this
time. Winds Should generally remain below 10kt, however, there
will be a short window of opportunity for winds to increase to
10-15kt in a small zone of stronger pressure falls as the low
moves across nrn MO into ern IA. The sfc low will then track
right over nrn IL, allowing winds to becm lgt/vrbl for a period
until the low lifts off to the northeast tomorrow morning and
winds veer from swly to nwly through the day. Have extended the
timing of ifr cigs through the day tomorrow. As sfc low pulls
away, some cooler/drier air should move in at the sfc, but still
expect vis to remain in the 1-3sm range and not improve above ifr
until drier air can move in late tomorrow afternoon and evening.
Some type of pcpn is likely to continue through the period.
Initially ra/shra with the short period of TS potential will
persist through the night. By tomorrow morning, expect some mid-
level dry air to overspread the region and pcpn should be more dz
than ra. Chances for sct shra will return for the afternoon as
more cyclonic flow aloft develops.
&&
.MARINE...
235 PM CST
Fog will continue to be a problem into Tuesday morning across the
southern part of the lake, especially the far south. Webcam
visibility and reports indicate near 1/2SM visibility, and have a
marine fog advisory now issued. There will be times when rain
showers abate some of the fog, especially this evening. However
there is a good possibility of the visibility dropping again
overnight.
Otherwise, this evening will see an increase in easterly winds
across the southern part of the lake. There could be a period
north of Chicago where winds and more so waves briefly reach Small
Craft Advisory criteria, but it should be short lasting. As the
low center moves over and past the lake, winds will turn northerly
across the entire lake, dissipating the fog. Winds turn southwest
on Wednesday and last into Thursday. Confidence in the wind
forecast Friday into the weekend is low, as trends are now
indicating more of an east to northwest wind given multiple slow-
moving low pressures to the southwest of the area.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...Dense Fog Advisory...ILZ019-ILZ020-ILZ021-ILZ022-ILZ023-ILZ032-
ILZ033-ILZ039 UNTIL MIDNIGHT Tuesday.
IN...Dense Fog Advisory...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL
MIDNIGHT Tuesday.
LM...Dense Fog Advisory...NEARSHORE WATERS
UNTIL 9 AM Tuesday.
&&
$$
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...Updated
National Weather Service Saint Louis MO
939 PM CST Mon Jan 16 2017
.UPDATE...
Issued at 926 PM CST Mon Jan 16 2017
A band of rain was moving through this evening from UIN southwest
to VIH. This precipitation was associated with a surface low near
UIN and a trailing cold front. This precipitation along with
stronger surface winds behind the cold front was leading to
improvement in the visibilities, and may be able to cancel the
dense fog advisory across parts of northeast MO and west central
IL early. Looking at the latest HRRR model runs it appears that
the rain should be east of the Mississippi River by midnight, then
east of our forecast area by 3 AM. Although the rain will come to
an end the cloud cover will continue to plague our area with
plenty of wrap-around type low level moisture and cloudiness
behind the surface low.
GKS
&&
.SHORT TERM... (Through Late Tuesday Afternoon)
Issued at 230 PM CST Mon Jan 16 2017
Surface low centered over northeastern KS will continue to lift
northeast tonight into the Great Lakes region by 12z Tuesday.
Associated cold front to slide through forecast area, exiting by
daybreak on Tuesday. Scattered showers will continue to develop
along and ahead of boundary, tapering off from west to east as front
moves through tonight. Decent MU CAPES between 250 and 500 J/kg, as
well as lift along and ahead of boundary, so will see some isolated
thunderstorms. Kept slight chance mention in grids for tonight.
Otherwise, cloudy skies to prevail with lows in the mid 30s to mid
40s. With such strong cyclonic flow around system, clouds to linger
over region on back side of system Tuesday, so highs will only be in
the upper 30s to around 50, which is still about 5 degrees above
normal for this time of year.
Byrd
.LONG TERM... (Tuesday Night through Next Monday)
Issued at 230 PM CST Mon Jan 16 2017
Weak surface high pressure will dominate the area on Tuesday
night as the short wave trof over the Great Lakes area departs to
the east, and this will probably be the coldest night of the week.
In the wake of this trof, heights aloft will be on the rise and the
surface high will be retreating eastward. A WAA regime gets underway
on Wednesday resulting from the combination of rising heights aloft
and the return of low level south/southwest flow. This will
bring a nice boost to the already above average temperatures.
After Wednesday, an increasingly energetic lower latitude storm
track emnanting from the Pacific will bring us several weather
systems thanks to a stout 150+ kt ULJ. Suprisingly, the models
are in reasonably good agreement with the large scale mass fields
depicting these systems during the longer range period. The first
of these will impact the area in the late Thursday-Friday time
frame as the positively tilted southwest U.S. upper trof and
embedded upper low eject east/northeastward and become negatively
tilted. The GFS is a tad slower with this sytem and hence the flow
aloft is more backed in the low levels and veered in the mid/upper
levels, which results in some variation in the depiction of the
warm conveyor belt, moisture transport, and resultant precipitation
threat. Basically we have followed a consensus approach at this
time. Moisture transport will begin on Wednesday night with the
main thrust from the lower MS Valley into the TN Valley region
into Thursday. Southeast MO and Southern IL will be the western
periphery with the greatest pcpn chances. The probability of
precipitation will increase and translate further west on Thursday
night with the approach of the actual upper system and negatively
rotating short wave.
Another upper low and trof will lift north/northeastward from the
southern/central Rockies and through the central U.S. on Friday
night and Saturday. Despite decent height falls and weak large
scale forcing for ascent with this system, moisture will be
negligible in the wake of the previous system. Friday night and
Saturday look largely dry and continued mild for later January.
Finally a potent upper low will evolve as it moves from the
southwest U.S. and impacts the area Saturday night into Sunday
night, bringing a good slug of rain. This would be a rather interesting
system and we would likely be talking winter storm IF temps were
much colder, however present progs suggest all rain and continued
above average temps.
Glass
&&
.AVIATION... (For the 00z TAFs through 00z Tuesday Evening)
Issued at 548 PM CST Mon Jan 16 2017
Surface low over west central MO with a trailing cold front
extending south through western AR. The low will move northeastward
through UIN later this evening dragging the cold front through the
rest of the taf sites later this evening. Band of showers and a
few storms moving through the St Louis metro area will shift east
of this area later this evening, while another area of rain and
embedded showers over the northwestern quarter of MO moves
northeastward through COU and UIN this evening. This second area
of rain may cause the very low visibilities from dense fog to
improve slightly in UIN later this evening. The stratus cloud deck
at 500 feet or less in height over the taf sites will continue
tonight and Tuesday morning, but should improve Tuesday
afternoon. The low visibilities due to fog should gradually
improve through the night into Tuesday. Southeasterly surface
winds will veer around to a westerly direction later tonight after
fropa.
SPECIFICS FOR KSTL: Surface low over west central MO with a trailing
cold front extending south through western AR. The low will move
northeastward through UIN later this evening dragging the cold
front through STL later this evening. Band of showers and a few
storms moving through the St Louis metro area will shift east of
this area later this evening. The stratus cloud deck at 500 feet
or less in height over STL will continue tonight and Tuesday
morning, but should improve Tuesday afternoon. The low visibilities
due to fog should gradually improve through the night into
Tuesday. Southeasterly surface winds will veer around to a
westerly direction late tonight after fropa.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...Dense Fog Advisory until midnight CST tonight for Knox MO-Lewis
MO-Marion MO-Monroe MO-Ralls MO-Shelby MO.
IL...Dense Fog Advisory until midnight CST tonight for Adams IL-Brown
IL-Pike IL.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Melbourne FL
759 PM EST Mon Jan 16 2017
.DISCUSSION...Main concern for tonight will be the potential for
patchy fog to develop across Volusia County and interior of east
central Florida into late tonight. High pressure ridge axis north
of the area will keep surface winds light out of the E/SE and
skies will be mostly clear. This will produce favorable conditions
for fog formation, but boundary layer winds off the surface remain
slightly elevated, which should help limit coverage. In fact the
latest runs of the HRRR and local WRF have not been too
enthusiastic on fog development across east central Florida late
tonight. Still, localized visibilities of a half mile or less
will be possible in some spots, mainly after 3AM through just
after sunrise Tuesday.
Low level onshore flow may generate a few sprinkles over the
coastal waters that can push onshore, mainly south of the Cape,
but coverage looks very limited and measurable rainfall looks
unlikely. Will therefore keep rain chances out of the forecast.
&&
.AVIATION...VFR expected through late evening. Patchy ground fog
will then be possible, mainly across the interior and Volusia
coast from late tonight into early morning Tuesday, with locally
dense fog possible. Any fog should diminish by mid morning, with
VFR conditions expected through the afternoon.
&&
.MARINE...
Tonight-Tuesday...(Previous Discussion) ESE winds 10-15KT will
veer to SE-S and slacken to around 10KT by late in the afternoon.
Continued very slow decay in swell, with seas 3FT near shore/5FT
well offshore slackening slightly to 2-4FT by late afternoon.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
&&
$$
Weitlich/Pendergrast
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
706 PM CST Mon Jan 16 2017
.UPDATE...
Issued at 641 PM CST Mon Jan 16 2017
Updated to include 00z aviation discussion below.
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 334 PM CST Mon Jan 16 2017
Precipitation, mainly light freezing rain, has been advancing/
developing northward through south central MN and adjoining areas
of western WI at near 20 knots through mid afternoon. The hourly
HRRR simulated radar forecasts have had a good handle on this
northward advancement. The northward advancement is expected to
end early this evening along a line from Redwood Falls through the
south Metro to near Cornell in west central WI with a more
eastward push there after. This is about the farthest north of any
of the solutions today, with quite a few deterministic/CAMS
stopping in Scott and Dakota counties early this evening. We added
a few counties to the winter weather advisory late this morning
based on earlier HRRR runs and this still looks good at this
point.
Surface temperatures have reached the freezing mark at mid
afternoon along the I-35 corridor from Albert Lea to Owatonna and
Waseca, helping to mitigate ice accumulation. It`s areas to the
west, north and northeast toward Eau Claire where icing is a
concern for travel over the next 3 to 4 hours. But even in these
areas, temperatures will likely rise to around freezing with even
some rain indicated with the HRRR. Once the system begins to
translate eastward this evening, (8-9PM), there will be a
changeover the snow and sleet and then to all snow. The best
corridor for snow accumulation during the late evening and early
morning hours on Tuesday stretches from St. James and Fairmont on
northeast through Eau Claire and Cornell with around an inch to an
inch and a half forecast.
A concern late in the night is that we will lose the ice in the
clouds but still have a saturated low level profile. Light
northwest surface winds will back to the northeast a few hundred
feet up along with increasing speed. This is a good situation for
freezing drizzle and we incorporated this into the late night
forecast.
Tuesday will be a somewhat better day weatherwise with the system
having departed off to the east. We will still have to deal with
considerable clouds early on. An issue that will need to be
watched is the threat for dense fog due to the light winds and
near surface saturation. Areas of central minnesota seem most at
risk for dense fog by daybreak.
Quite a range in lows tonight due to the differences in cloud
cover/precip across the FA with lows ranging from the single
digits above zero in Alexandria to around 30 for the Twin Cities
on east and south. Quite a range on Highs for Tuesday as well with
25 to 30 for western MN with 30 to 35 for eastern MN and western
WI.
.LONG TERM...(Tuesday night through Monday)
Issued at 334 PM CST Mon Jan 16 2017
The January thaw will commence this week, and last through the
weekend before some modification to the mean temperatures next week.
First, the positive long wave trough that has allowed for tonight`s
system to move from the desert southwest, into the Plains, and
eventually into the northeast, will be followed by another upper low
moving out into the Plains late this week. Depending upon a
developing upper ridge over the Great Lakes which strengthens or
moves northward this weekend, will be dependent on the next upper
low movement across the Plains early next week.
Secondly, both the GFS/EC favor the southern jet stream energy
through this week, and into early next week. This will keep the bulk
of the significant weather across the central/southern Plains, and
into the Midwest. The northern jet stream will be concentrated in
Canada through Thursday allowing for wet/stormy weather for the
Pacific Northwest, and western Canada. However, the long wave
pattern becomes more problematic late in the week, and into the
weekend as a long wave trough and associated unsettled weather moves
further south across the western U.S.. Eventually the western U.S.
will become more active which has been the case this winter.
For our region, other than a weak system late Friday/early Saturday,
the bulk of the week will remain dry and unseasonably mild. With the
snow pack across Minnesota and western Wisconsin expected to slowly
melt, the forecast challenge would be fog and low cloud development,
and minimal diurnal temperature swings from overnight lows and
daytime highs. The forecast highs/lows this week and into the
weekend have been modified some for a milder outcome. I would not be
surprised to see a period where the temperatures in southern
Minnesota do not fall below freezing for a couple of days.
As with the previous forecast elaborated on record high/low
potential later this week, and into early next week, I wouldn`t be
surprised to see highs approaching records, but due to the snow pack
and low sun angle, it doesn`t seem likely. There is a better
potential of overnight lows not dropping before freezing. Therefore,
record low maximums could be in jeopardy.
The longer range past the next 7 days does support more seasonable
temepratures which are highs in the 20s and lows around 10-15
degrees. As the transition of more seasonable temperatures and an
active weather pattern developing next week, additional snowfall
becomes more likely.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 641 PM CST Mon Jan 16 2017
Large precipitation shield shifting north this evening is
spreading FZRA into MSP-RNH-EAU while RWF-STC-AXN looks to
generally remain dry but will be more susceptible to fog and low
stratus development with virtually calm winds overnight. All sites
look to hit IFR levels by daybreak if not earlier with the FZRA
for the eastern sites to potentially mix with and change over to
-SN later this evening. There is also a small chance of leftover
FZDZ in the pre-dawn hours but by and large the precipitation
should be overnight by daybreak with only fog/stratus left over.
Conditions will steadily improve during the day tomorrow back to
VFR.
KMSP...Already seen FZRA reported at MSP and will likely continue
to have FZRA through at least 02z-03z before precipitation changes
over to -SN. -SN is then expected to continue for several hours
until after midnight. Potential for some FZDZ approaching the
Tuesday morning push but confidence is more medium than high in
this scenario. Regardless, IFR ceilings with MVFR visibility due
to fog/stratus may well persist before conditions steadily improve
late morning into afternoon hours.
/OUTLOOK FOR KMSP/
Wed...VFR. Winds SW 5-10 kts.
Thu...VFR. Winds S 5-10 kts.
Fri...VFR. Slight chance of MVFR and -RA. Winds southeast around 5
mph.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...Winter Weather Advisory until 6 AM CST Tuesday for WIZ023>028.
MN...Winter Weather Advisory until 6 AM CST Tuesday for MNZ060-062-
063-066>070-074>078-082>085-091>093.
&&
$$
UPDATE...JPC
SHORT TERM...RAH
LONG TERM...JLT
AVIATION...JPC
Area Forecast Discussion
National Weather Service Marquette MI
656 PM EST Mon Jan 16 2017
.SHORT TERM...(This evening through Tuesday)
Issued at 344 PM EST MON JAN 16 2017
Water vapor imagery and RAP analysis show a well-defined shortwave
over eastern KS lifting slowly ne across the Central Plains.
Another shortwave moving ese across the Dakotas and Manitoba may
play a role in the track of the southern stream wave over the next
24 hrs. Current confluent flow across the area resulting from the
ridging ahead of the southern stream wave and the more zonally
oriented flow from south central Canada to New England is supporting
sfc high pres ridging/deep dry air mass from MN eastward across
Lower MI as noted on 12Z area soundings. Mid clouds are beginning to
spread into Upper Mi today ahead of the southern shortwave
approaching the Great Lakes, but the amount/extent of pcpn from this
wave reaching into Upper Mi will largely depend on steering
influence from northern stream wave and also how long dry very
airmass in place will take to moisten.
Tonight and Tuesday, attention turns to the what impact the southern
stream shortwave will have on the fcst area. Models are in fairly
good agreement on the flow aloft, indicating that the shortwave
currently over Dakotas/Manitoba will drop se, but not really have
much interaction/steering influence on the southern stream wave to
pull it sharply N. Consequently, models in good agreement that the
southern wave will track ne, passing across SE Lower MI Tue morning.
As isentropic ascent/deep layer forcing lifts N and weakens while
approaching Upper MI tonight, antecedant dry air mass will have an
impact on slowing and diminishing the approaching pcpn area. That
said, 12Z models and SREF QPF fields in pretty good agreement that
far southern Menominee County could receive up to .2 inch of QPF but
then QPF amounts taper off quickly to the north with generally
.1 inch or less of QPF into northern Menominee county and across the
rest of the counties bordering Lake Mi and the bay of Green Bay.
Thus, forecast will reflect a sharp gradient from categorical pops
over southern Menominee County tapering to schc pops reaching no
farther N than roughly an Iron River to Newberry line. As for ptype,
fcst soundings for Menominee from the RAP/HRRR/NAM/GFS show a deep
isothermal layer around 0C once saturation occurs. Result would be
all snow if it`s no warmer than 0C, but if the deep layer is just
above freezing, then pcpn would likely be FZRA. The warmer Canadian
model and deeper isothermal layer above freezing would further raise
the prospect for mostly FZRA as ptype, which NAM sounding for MNM
generally supports as well particularly late tonight. Given that
most of the model soundings support as least some period of FRZA
over southern Menonimee County, have decided to issue a winter
weather advisory for Menominee County from late this evening into
Tue morning. Given that QPF amounts are much lighter farther north
into Delta and Schoolcraft counties will not issue a headline for
mixed pcpn there. Dickinson, Iron and southern Marquette and
southern Alger will be on northern fringe of pcpn shield with only a
dusting of light snow expected.
Temperatures are expected to rise above freezing by Tue afternoon so
threat of freezing rain will subside at that point. Also forcing
from weakening system will be lifting e and out the area so
expect pcpn in general to be quickly diminishing.
.LONG TERM...(Tuesday night through Monday)
Issued at 354 PM EST MON JAN 16 2017
Warming temps will be the main story of any confidence in the long
term as an upper ridge builds into the area through late week. Highs
will be in the mid 30s to around 40 Wed and Thu. Lows will increase
from around 20 Tue night to the mid to upper 20s Wed night and Thu
night. By the weekend, rain is possible as multiple waves move
through the region, but confidence is quite low. Highs will be
around 40 with lows above freezing over the weekend, possibly
cooling down a bit on Mon. Overall, with good model agreement into
Fri then low confidence after that, the blends did well so stuck
close to blended solution.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 656 PM EST MON JAN 16 2017
A deep dry air mass currently over Upper MI will continue to prevail
at KIWD/KCMX/KSAW through this forecast period, resulting in VFR
conditions.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 344 PM EST MON JAN 16 2017
Winds diminish to under 15kt and remain mostly under 15kt thru Tue
as the pres gradient remains weak across the area due to sfc ridging
across the area. Winds may increase upwards of 20-30kt late Tue
night into Wed as the sfc ridge moves east and sfc trough pushes east
from the Northern Plains. For the remainder of the week, expect
winds mostly 20kt or less as conditions become unseasonably warm over
the Upper Lakes with no significant weather features impacting the
area.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Winter Weather Advisory from 10 PM this evening to 11 AM CST
Tuesday for MIZ012.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Voss
LONG TERM...Titus
AVIATION...JLB
MARINE...Voss
Area Forecast Discussion
National Weather Service Norman OK
927 PM CST Mon Jan 16 2017
.DISCUSSION...
Low clouds from the north have continued to move south into the
northwest half of Oklahoma, similar to the HRRR forecast. Gridded
forecasts were updated to give a slightly more southward extent to
the low clouds before moving them off to the northeast around
sunrise. Temperatures trends were adjusted slightly given
observations a bit cooler and in line with the HRRR.
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 31 50 36 55 / 0 0 20 10
Hobart OK 30 51 36 57 / 0 0 30 10
Wichita Falls TX 32 53 37 56 / 0 10 50 10
Gage OK 27 47 32 56 / 0 0 10 10
Ponca City OK 31 47 31 55 / 0 0 10 10
Durant OK 37 53 40 53 / 0 10 40 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...None.
TX...None.
&&
$$
09/25