Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/05/17
Area Forecast Discussion
National Weather Service Billings MT
820 PM MDT Wed Oct 4 2017
.UPDATE...
An area of light rain exists from Billings westward toward the
Crazy Mountains, and showers are beginning to develop near Hysham
and Lame Deer. This activity is in response to ascent provided by
shortwave lifting out of a slow-moving parent low over the
northern Great Basin. Have adjusted evening pops to cover radar
trends. Overall this activity should slide north over time
tonight, and mostly diminish by sunrise, as descent works in from
the southwest behind the wave. With at least some partial clearing
expected in our western cwa overnight, cannot rule out some
patchy fog as the current precipitation is helping to moisten the
boundary layer (current dew points are in the mid- upper 30s). The
HRRR is not suggestive of fog at this time. Will be another fairly
chilly night with lows in the 30s. JKL
&&
.SHORT TERM...valid for Thu and Fri...
Upper low over Idaho will swing some energy through our CWA
tonight. Moisture is mainly at the mid levels, but lapse rates
are steep enough to support rain/snow showers over the mountains
and isolated shower activity over the plains, maybe even a little
thunder here or there. The jet stream nosing into the SE zones
may even support a band of precipitation Thursday night and into
Friday, but by late Friday the upper low weakens and its axis
shifts east to the Great Plains. Look for warmer temps Friday in
its wake.
We are in the autumn season so things will transition quickly
Friday night. The northern jet quickly drops south into northern
Montana with a tight pressure gradient developing southeastward
into our area. Our western foothill locations will likely see the
first effects, particularly at the gap locations (Livingston,
Nye). There is potential for wind advisory criteria Friday night
into Saturday at these sites. As a matter of fact, by late Friday
night/early Saturday morning strong 850MB wind fields are progged
to spread across NW to SE across our central and eastern zones.
The westerly jet stream will be nosing right across east central
Montana at this time with downward motion in the front right quad
over our eastern zones. Lapse rates suggest these winds could
impact areas from eastern Musselshell to northern Custer County
with strong gusts. See long term discussion below for further
information on winds this weekend. We will begin messaging the
windy conditions in some of our other products and on our website.
BT
.LONG TERM...valid for Sat...Sun...Mon...Tue...Wed...
Only a few minor tweaks to the inherited long term forecast, as
overall story remains consistent.
Timing of models for Saturday appears in better agreement for
later FROPA, resulting in warmer temps across the region.
Therefore, trended temps upward for Saturday, with highs around 70
in most locations across the plains. It continues to look windy
for Saturday, both before and after FROPA, with gusts over 60 mph
in the western foothills pre- FROPA, and a windshift and gusty
northwest winds to follow FROPA across the plains. Expect to see scattered
showers for a couple of days following, with snow in the
mountains, which could drop into the lower elevations during the
overnight hours. There could be a few thunderstorms mixed as well
on Sunday afternoon. The airmass in place for Sunday and Monday looks
quite cool, with 850mb temps of 4 to 5 C, pointing to highs in
upper 40s Sunday. Strong West Coast upper ridge builds into the
area late on Monday providing a bit of a warm up to get temps back
into upper 40s. Dry and breezy conditions can be expected for
Monday evening through Wednesday under the ridge. Temps will trend
upward through the end of the forecast period.
On the far horizon models starting to hint at a significant cold
air intrusion late next week. Models do differ, but agreement
is reasonably good for this far out in time. We will be watch this
development closely ver the next week or so. AAG
&&
.AVIATION...
Expect mainly VFR conditions to prevail. Scattered showers are
moving from southwest to northeast across the area and will
continue to overnight. Brief MVFR conditions are possible with
these showers. Some patchy fog is possible mainly after 06z,
especially around KLVM. Reimer
&&
.PRELIMINARY POINT TEMP/POPS...
Thu Fri Sat Sun Mon Tue Wed
-----------------------------------------------------------
BIL 036/056 037/067 046/069 039/050 033/048 029/053 037/058
50/B 00/U 01/N 23/T 22/T 11/U 00/U
LVM 032/053 032/062 042/065 034/043 026/044 026/050 032/056
31/B 10/N 01/N 24/T 32/T 11/U 00/U
HDN 035/058 036/067 043/072 038/052 034/049 030/054 036/061
10/B 00/U 01/N 23/T 22/T 11/U 00/U
MLS 036/056 037/066 044/069 038/052 033/047 028/049 034/057
20/U 01/U 01/N 12/T 11/B 11/U 00/U
4BQ 036/057 037/064 042/070 039/051 034/045 028/048 034/057
20/U 01/B 01/N 23/T 22/T 11/U 00/U
BHK 037/057 037/064 043/068 037/052 032/043 027/047 032/054
20/U 01/U 01/N 12/T 12/W 11/B 10/U
SHR 033/056 035/063 039/072 037/048 030/045 027/050 032/059
10/U 11/B 01/U 34/T 22/T 11/U 00/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...None.
WY...None.
&&
$$
weather.gov/billings
Area Forecast Discussion
National Weather Service Caribou ME
1031 PM EDT Wed Oct 4 2017
.SYNOPSIS...
A cold front will cross the area overnight followed by a
secondary cold front Thursday night. High pressure will build in
from the west on Friday and crest over the area Friday night.
&&
.NEAR TERM /THROUGH THURSDAY/...
1030 PM Update...
A large area of rain moving across the region w/some embedded
tstms. Most of the convection has started to weaken per the
latest lightning data showing less strikes. Meso analysis
indicated convective parameters such as MUCAPE weakening. There
is still some shear noted from the latest 00z CAR RAOB of 35
kts. The RAP soundings matched close to the CAR RAOB and
indicate that some elevated convection still possible up through
midnight or so. The main threat looks to be some heavier bands
of rain through about 2 AM. The cold front is still w of the
state and expected to push through the area by Thursday morning.
Some cooler air is expected to move into the region by
daybreak.
Decided to keep the mention of heavy rain in the forecast up
through about 1 AM along w/some gusty winds. Also adjusted the
QPF blending in the latest values from the NERFC bringing around
0.50 inches of rainfall to portions of the n and w. A well
needed rainfall for the region. Also adjusted the pops to bring
values up some across central and downeast areas.
Previous Discussion...
With cld cvr and not much in the way of llvl cool advcn and a
WNW breeze behind the front, ovrngt lows will be mild for this
tm of year. Hi temps Thu under msly sunny skies will be about 10
deg cooler across the N to 5 deg cooler Downeast than this
current aftn with a fair Wrly breeze, still sig abv normal hi
temps and quite pleasant for this tm of season.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
A cold front will approach Thursday evening and cross the area
Thursday night. This weak secondary cold front will have very little
moisture, and likely only produce a few patchy mid and high clouds.
High pressure will build in from the west on Friday bringing a
mostly sunny and seasonable afternoon. The high will crest over the
area Friday night allowing for a clear, calm, moonlit night as
temperatures fall below freezing in many northern valleys. High
pressure will move east of the area on Saturday as a broad trough of
low pressure approaches from the west. This will begin to channel
subtropical moisture north toward our area. A warm front will lift
north into the area late Saturday bringing a chance for some showers
as a surge of increasingly humid air lifts north toward our region.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
The start of the extended finds the models in general agreement. A low
over the southern portions of James Bay, With a warm front
extended southeast into northeast Maine, the associated cold
front extending south to the gulf of Mexico. A tropical low will
be interacting with the southern end of the front south of
MS/AL. Sunday morning the cold front sweeps through northern
Maine, and will be across Downeast, the MidCoast, and Southwest
Maine as it extends southwest where the tropical low will become
attached to the front along the coast of MS/LA (GFS), central
MS (GEM) or the Panhandle of FL (ECMWF). Higher pressure will
build across Maine, The cold front will be brought back across
Maine as a warm front as the tropical low moves north into the
western portions of VA Monday morning. By Monday evening it will
move into the Gulf of Maine south of Portland, then drift
southeast to the south of Nova Scotia Tuesday morning. A low
over Lake Superior Tuesday morning will move east to central
Quebec by Wednesday morning bringing a cold front into western
Maine. The cold front will move through Wednesday night and
higher pressure will remain across the area through the end of
the period.
Loaded a blend to smooth out the differences in the models,
however the solution leans more towards the GFS solution. Used
NAWAVE4 for seas in the coastal waters. Used windgust by factor
tool.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
NEAR TERM: Current VFR conditions will transition to MVFR clgs
and ocnly, vsbys with shwrs this eve into the ovrngt spcly Nrn
TAF sites. All TAF sites should become VFR late tngt behind the
cold front and then cont so thru Thu.
SHORT TERM: VFR conditions are expected Thursday night through
Saturday morning. Conditions may lower to MVFR from south to
north Saturday afternoon as ceilings lower ahead of an
approaching warm front.
&&
.MARINE...
NEAR TERM: Will cont with the SCA for our outer MZs, with the
ending extended til noon Thu, at which point, both winds and
seas should begin to subside. Kept close to WW3 wv guidance for
this fcst update thru Thu with primary wind wv pds of 5 to 7
sec.
SHORT TERM: Winds and seas are expected to be below SCA through
Saturday morning. A southerly winds will increase with the
approach of a warm front late Saturday and winds may reach SCA
late in the day.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...Small Craft Advisory until noon EDT Thursday for ANZ050-051.
&&
$$
Near Term...Hewitt
Area Forecast Discussion
National Weather Service Duluth MN
840 PM CDT Wed Oct 4 2017
.UPDATE...
Issued at 840 PM CDT Wed Oct 4 2017
Temperatures have been cooling quickly this evening and were
lowered for most areas. We expanded the Frost Advisory across much
of far northern Minnesota and will watch temperatures over the
next 1 to 2 hours for possible additional expansion.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 354 PM CDT Wed Oct 4 2017
At 330 PM, skies ranged from cloudy across the international
border region, to mostly clear across the far south. We did have
extensive cloud cover for most of the CWA today, but the clouds
were starting to break up, especially across the south.
Temperatures were generally in the 50s with gusty west winds.
The focus for tonight is on cloud cover, and the potential for
frost across portions of the region. The general consensus among
the various model solutions is that the clouds will continue to
clear across the Northland tonight. Most guidance indicates the
coolest temps are expected to be in Koochiching and Northern
Itasca county tonight, and as a result, we have issued a Frost
Advisory for that area. The gusty winds will also diminish
tonight, giving us further cause to issue the Frost Advisory.
For the southern half of the CWA, we should see an increase in mid
and high clouds as the night wears on. The big question is whether
we will see any precipitation late tonight across the south, with
the RAP indicating some QPF in the Brainerd Lakes to Pine City
area. A few of the other CAMs are also indicating the potential
for some light rain across our southern MN counties. At this point
we will keep the forecast dry, but keep a close eye on it.
Some light rain may skirt our southern counties on Thursday, but
the vast majority of the rain should be south of our CWA. The rest
of the area will see conditions range from partly to mostly sunny
north to cloudy in the south. Temperatures will be limited a bit
due to the cloud cover, especially in the south.
.LONG TERM...(Thursday night through Wednesday)
Issued at 354 PM CDT Wed Oct 4 2017
A cutoff low over the western United States will slowly open and
progress eastward late this week into this weekend. As trough moves
into the western Plains on Friday, surface cyclogenesis will take
place over Colorado. The poleward transport of moisture ahead of the
burgeoning storm system will bring clouds, along with showers and
thunderstorms into the Northland. The surface low will continue to
strengthen as is moves northeastward into western Iowa by Friday
night. A corridor of moderate rainfall is possible from the I-35
corridor east across northwest Wisconsin. Rain and thunderstorms
will taper off Saturday afternoon, but due to already saturated
soils over the aforementioned areas, the rainfall may lead to
areas of flooding.
A fast-moving shortwave trough will push through the Northland
Sunday night and Monday. A variety of solutions are available today
with the GFS bringing a slow and very wet system through the region,
while the ECMWF is slower and weaker. The GEM splits these
solutions. Stuck with a consensus blend for now due to low
confidence. Very cool temperatures aloft in the GFS raise the
spectre of light snow mixing into the back side of the Monday
system. For now, have followed the trend of the previous shift and
removed snow mentions due to low confidence. Will need to keep an
eye on these trends over the next few days. Should the GFS solution
be close to reality, portions of north-central Minnesota may see
their first dusting of snow Monday night.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 640 PM CDT Wed Oct 4 2017
An area of high pressure will move east and south of the region
tonight with a trough and shortwave replacing the high with the
main impacts just south of the Northland. Clouds will continue to
clear this evening from southwest to northeast with additional VFR
ceilings moving back into southern areas later tonight and further
north on Thursday. Some fog will be possible but we don`t expect
widespread fog overnight. Showers will develop over parts of
central Minnesota into central and northern Wisconsin. However, we
expect KBRD and KHYR will be dry through the period.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 41 58 40 57 / 0 0 0 30
INL 34 55 32 58 / 0 0 0 10
BRD 40 58 40 57 / 0 0 0 50
HYR 38 58 39 60 / 0 10 10 40
ASX 41 59 40 61 / 0 0 0 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...Frost Advisory from midnight tonight to 9 AM CDT Thursday for
MNZ010>012-018-019.
LS...Small Craft Advisory until 4 AM CDT Thursday for LSZ145>147.
&&
$$
UPDATE...Melde
SHORT TERM...DAP
LONG TERM...Huyck
AVIATION...Melde
Area Forecast Discussion
National Weather Service Quad Cities IA IL
1055 PM CDT Wed Oct 4 2017
.UPDATE...
Issued at 1053 PM CDT Wed Oct 4 2017
Additional updates have been issued as confidence on dry weather
is increasing tomorrow. It looks like the front, which is in
central MO, will remain south, and keep the focus of rainfall far
away from the area after the wave currently in our south and over
central Illinois passes east. Thus, I have taken a wet day of our
forecast and reduced it to a chance of showers. This may also
allow tomorrow night`s event to miss most of the northern 1/2 of
the CWA or more.
ERVIN
UPDATE Issued at 923 PM CDT Wed Oct 4 2017
Elevated showers are being indicated over the southern 2 tiers of
counties as of 9 PM, and scattered showers are now sped up in
arrival time to reflect this. AT the moment, activity is so light
it`s probably sprinkles, but the wave passing seems to be
saturating on target to the recent HRRR runs, and that suggests
this activity will continue into the night, along the elevated
warm front.
ERVIN
&&
.SYNOPSIS...
Issued at 330 PM CDT Wed Oct 4 2017
The latest sfc analysis was indicating 1030+ high presssure center
slowly settling acrs the upper MO RVR Valley, while the main front
was pushing south and east of the local area. Flattened flow/
westerlies continue to adjust from the northern plains through the
eastern GRT LKS, with vort max embedded southwesterlies arching up
acrs the central Rockies into west central plains. With eventual
moisture feed from the south combining with waves electing out of
the southwesterlies and along the quasi-stationary front for a
potentially significant rain regime into Saturday.
&&
.SHORT TERM...(This Evening through Thursday)
ISSUED AT 330 PM CDT Wed Oct 4 2017
Tonight... with the sfc front currently settling acrs central MO and
orienting from west-to-east, just a low chance for an isolated
elevated shower moving up out of Mo and acrs the southern CWA
through midnight. The main overrunning cloud shield will continue
from just north of I80 and southward as well, allowing the northern
third of the DVN CWA to cool quickly after sunset as winds go light
northerly while ridge center slides east toward southwest WI. As a
lead vort max shuttles east acrs northern MO and isentropic lift
increases along with some return flow signals(such as the MO sfc
front retreating back north some into Thu morning), could see an
uptick in elevated showers acrs the southern third of the CWA late
tonight after midnight into early Thu morning. dry air feed from the
north should limit a further north precip progression or keep them
mainly as virga up along and north of I-80. Wide range of low temps
overnight, with areas of the far north which stay mainly clear the
longest cooling into the mid 40s, while the cloudy south stays up in
the mid to upper 50s. The MET/NAM MOS even points to some lower 40s
in the far north.
Thursday...Sharp H8 to H85 MB inversion that forms overnight lasts
well into Thu. Continued upper level wave feed out of
southwesterlies allows fro more sfc cyclogenesis acrs the central
plains as Thu progresses, which acts more upon the boundary for a
northward retreat into at least the southern third of the CWA by
late Thu afternoon. continued moisture feed, upward vertical
velocities and saturation by incoming synoptic scale lift regime,
should make for more increased shower coverage and spreading north
as the day progresses. Thus the warrant for high afternoon POPs.
With the initial dry sub-H8 MB layer to overcome, most areas that get
rain will average from around a tenth of an inch, to pushing a half
inch of rainfall by 00z Fri. Most areas probably on the lower part
of that spectrum. A few models suggest that at least during the
afternoon enough elevated MUCAPES to support isolated thunder
embedded in the showers/rain especially west of the MS RVR. East to
south east sfc winds, clouds and evapo-cooling from the precip to
limit many areas to highs in the 60s, maybe the fare south closer to
frontal passage and some WAA makes it into the lower 70s. ..12..
.LONG TERM...(Thursday Night through next Wednesday)
ISSUED AT 330 PM CDT Wed Oct 4 2017
Wet forecast to begin the period followed by more seasonal weather
and another cold front late in the period. Long duration stratiform
rain with embedded thunder event will start the period and last
through fropa on Saturday across the area. The quiet weather is
forecast until Monday into Tuesday when another front moves into the
area.
12Z Guidance suggests that the best threat for precip will occur
along and south of I80 through Friday morning. Upper level dynamics
and LLJ favor precip to our west and south. As the upper level wave
shifts to the east, the threat for more widespread rainfall will
increase. Friday night, a H85 jet over 50 kts along with PW values
near 2 inches will lead to moderate rain across the area. A cold
front is forecast to move through on Saturday and will end our
chances of rain. Have high confidence rainfall across the southern
CWA across our south and west and then area wide Friday into
Saturday. Overall confidence in the amount of rain is low.
Conditions look favorable for a PRE to develop as the tropical
system recurves to our south this weekend. Guidance suggests that
this PRE will develop to the east of the area. Questions of what
this convection may do to our moisture feed seem reasonable. This
will need to be watched through the next 48 hours as guidance on the
tropical system track in the Gulf still has considerable spread.
This weekend, cooler temps will prevail before a small warm up on
Sunday as our next cold front approaches the area. H85 temps at or
below 0 are possible into midweek next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday Evening)
ISSUED AT 606 PM CDT Wed Oct 4 2017
Dry low level air will help keep VFR conditions going tonight,
through Thursday morning. A warm front will begin to lift north
Thursday, with light rain spreading over eastern Iowa during the
afternoon. Some isolated thunder is possible, but not well
forecast at this time, and only rain is included in TAFs. BRL, as
well as southern Iowa, will be close enough to the warm front to
see lower MVFR CIGs from late tonight through Thursday, while the
northern areas are expecting much higher CIGs through the period.
ERVIN
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...Ervin
SYNOPSIS...12
SHORT TERM...12
LONG TERM...Gibbs
AVIATION...Ervin
Area Forecast Discussion
National Weather Service Grand Rapids MI
1053 PM EDT Wed Oct 4 2017
LATEST UPDATE...
Marine
.SYNOPSIS...
Issued at 325 PM EDT Wed Oct 4 2017
A lull in the rain chances will occur tonight and through the first
half of Thursday, but then there will be several chances for rain
starting Thursday afternoon and lasting through Saturday. We should
dry out for the end of the weekend, with the next chance of rain
holding off until Tuesday and Tuesday night. Temperatures are
expected the stay mainly above normal in the 70s, with a couple days
in the 60s for highs over the next week.
&&
.SHORT TERM...(This evening through Friday night)
Issued at 325 PM EDT Wed Oct 4 2017
THe front and showers were exiting the CWA this afternoon. This
lull will last until Thursday afternoon/evening, then rain chances
return, peaking Friday afternoon and night.
After a dry period tonight, the forecast has trended a bit drier for
Thursday. The front will sag a bit farther south, with a weak area
of high pressure moving across the CWA early Thursday. The return
north of the front will be delayed until Thursday night, when it
moves from Central IN to the northern part of the state. The front
then moves north across Southern Lower Friday. Solid moisture
advection follows for Friday night.
As the front moves north Thursday night, we should see a few
isentropic lift showers break out late afternoon or early evening
and these should continue overnight. The best moisture and lift
seems to pool toward Central Lower initially, but this merges
farther south with the front as the night goes on. The highest
chance of showers should occur south of I-96 late Thursday night.
We should see a brief lull in the rain as the front moves north of
the CWA on Friday, but by late day we begin to see the better
moisture advection returning. Along with a coupled jet feature by
late day, the rains should see higher coverage, especially south of
Highway 46 by late afternoon/early evening.
The strongest surge of moisture and lift comes Friday night. We
will be in the heart of the moisture advection by this time frame.
Surface low pressure will be moving out of IA and into WI. This
feature and the upper jet will continue to support healthy lift.
Precipitable water values climb to around 1.5 inches by Friday
evening and through Friday night.
With the ample moisture arriving it is expected that most areas see
around a half inch of rain, with much of that coming Friday
afternoon and night.
.LONG TERM...(Saturday through Wednesday)
Issued at 325 PM EDT Wed Oct 4 2017
A low pressure system will move northwest of the region and pull a
cold front across the area Saturday into Saturday night. A lack of
instability with the front may limit the weather to showers with no
lightning.
After a break in the weather Sunday into Columbus Day, another low
is expected to follow a similar path across the region, bringing
precipitation and possibly thunderstorms late on Columbus Day into
Tuesday night.
Temperatures will be above normal into Tuesday and then cool to a
little below normal by Wednesday. Normal highs are in the lower 60s
and normal lows are in the lower 40s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 739 PM EDT Wed Oct 4 2017
Skies should become clear at all TAF sites by 03z and remain so
till around 18z Thursday. There is a slight risk of fog toward
morning but at this point it seems to questionable to actually put
in the TAF forecasts. If there is fog the I-94 taf sites would be
the most likely since it rained more significantly there and the
clouds did not clear there till after sunset.
The low clouds have been slow to clear along the I-94 TAF sites
late this afternoon but the latest satellite image loops and RAP
and HRRR model data suggest this area of clouds will clear the
area by 03z or so. For the most part once the skies nearly do
clear (risk of fog AZO, BTL and JXN 09z till 13z) I expect clear
skies across the area into late morning Thursday. Then mid level
clouds will move in ahead of the next frontal wave heading this
way. Skies will become overcast around 5000 ft agl at most if not
all taf sites by 21z. No rain is expected until after 00z Friday.
&&
.MARINE...
Issued at 1052 PM EDT Wed Oct 4 2017
I have ended the small craft advisory since winds are generally
under 15 knots and even at Ludington the significant wave heights
have fallen below 3 feet.
&&
.HYDROLOGY...
Issued at 325 PM EDT Wed Oct 4 2017
Dry weather will become reestablished over west Michigan tonight in
the wake of a cold front and as a brief ridge of high pressure
builds over the area. The front will slowly lift back northward
through the end of the week, providing increasing chances for
rainfall starting Thursday afternoon. The best potential for rain
looks to be between Friday afternoon and Saturday evening, when
amounts could reach over one-half of an inch.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...None.
&&
$$
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...63
AVIATION...WDM
HYDROLOGY...HLO
MARINE...WDM
Area Forecast Discussion
National Weather Service Houston/Galveston TX
928 PM CDT Wed Oct 4 2017
.DISCUSSION...
At 01z, an area of low pressure was over NM with high pressure
over the eastern US with a light east wind. At 850 mb, a strong
area of high pressure was noted over the eastern US and 850 temps
have cooled a bit at LCH with temps down to 15 C. At 300 mb, a
sprawling ridge of high pressure was located over South Texas. A
few isolated showers linger near the coast but these will become
less numerous with time. Not a lot of change to the current
forecast with unseasonably warm temps and dry conditions through
Sunday. Made some minor tweaks to the grids to match obs but the
integrity of the previous forecast is on track. 43
&&
.PREV DISCUSSION... /ISSUED 626 PM CDT Wed Oct 4 2017/
AVIATION...
VFR conditions are expected for most areas tonight and Thursday.
Patchy areas of MVFR are possible mainly between 09Z and 13Z at
the more rural sites of KCXO and KLBX. Isolated showers could
affect KGLS through 02Z and overnight through early morning
Wednesday from 06Z to 13Z.
40
PREV DISCUSSION... /ISSUED 354 PM CDT Wed Oct 4 2017/
DISCUSSION...
Relatively quiet forecast for several days with little to no
potential for precipitation and above normal temperatures. Much of
the focus will be on this weekend and early next week as we watch
the progress of Tropical Depression 16 and a cold front for early
next week. At this time it appears that TD 16 will not track far
enough west to cause direct impacts to our area, but there is still
a fair amount of spread in the guidance, and it will be important
even in Southeast Texas to monitor the latest forecast information
from the National Hurricane Center to ensure that expected level of
impact continues. Beyond that, we`ll be anticipating the arrival of
the next cold front from the northwest, which will increase rain
potential on/ahead of the front, but bring cooler and drier air for
the mid-week behind it.
NEAR TERM [Through Tonight]...
Radar is showing a couple weak showers over Jackson County this
afternoon, but drier air has pushed in over much of the area from
the northeast, and combined with a cap around/below 700 mb in HRRR
soundings, that has kept the vertical growth of clouds in check for
most today. Can more or less expect this to continue through the
rest of the day and into tonight, though some nocturnal activity
over the Gulf waters may pop up.
SHORT TERM [Thursday Through Friday Night]...
Midlevel ridge over Texas should slowly slide and weaken southwest
while a northern stream trough digs over the Rockies. Roughly
easterly flow will continue far to the north of developing TD 16,
aided by high pressure over the Carolinas. Precipitable water is
progged essentially unanimously to continue to fall, potentially
even below 1 inch, keeping fair weather in the forecast. Though the
midlevel ridge is expected to begin weakening, it should impart
enough subsidence and fair skies for continued above normal
temperatures across the area.
LONG TERM [Saturday Through Wednesday]...
Changes are afoot for the weekend into early next week. Much of the
weekend forecast will be extremely dependent on the precise path of
TD 16, even if it does not come close enough to give us direct
impacts. Guidance on the left edge of the 16 envelope, like the GFS,
crank up PW on the outer edge of the storms`s moisture envelope, and
bring back potential for scattered showers and storms over Southeast
Texas as we look at a setup with onshore flow and higher moisture.
On the flip side, more eastern guidance like the Euro keep us more
on the subsident outer edge of the storm, with lower moisture
content and flow that is roughly shore parallel.
As best I can tell, much of the difference in track for this portion
of the forecast hinges on 16`s interaction with a wave/upper trough
that crosses the Gulf of Mexico in advance of 16. The GFS is much
stronger with this feature, even inducing a bit of a Fujiwara
effect between the two lows, which pulls the GFS towards the left
side of the envelope. Additionally, it is now nearly 24 hours
slower than the Euro with the approach of the northern trough and
cold front which also slows steering currents ahead of it, also
allowing the storm to drift more towards a Louisiana landfall.
While plausible, the Euro`s picture of a weaker leading wave and
faster frontal timing seem more realistic, so the forecast leans a
bit harder in that direction. This puts the front through the
area along with highest rain chances on Tuesday. Cooler and drier
air should come in behind the front, knocking temperatures to near
or a little below normal.
MARINE...
East winds 15 to 20 knots will prevail through the night with long
period swells of 3 to 7 feet and some wind wave on top. Will carry a
SCEC nearshore and SCA 20-60nm. The winds should relax slightly
Thursday afternoon. A few showers will prevail tonight with deeper
moisture confined to the airmass over the water thanks to the upper
ridging over TX/LA/AR.
This persistent easterly flow with the long period swell will
maintain elevated tide levels and strong rip currents for the Upper
Texas Coastal waters through Thursday morning and probably into the
evening hours...so have extended the CFW Beach Hazard Statement.
Light winds Friday night through Sunday night...followed by a potent
cold front (for this time of year) which will boost winds Monday
night or more likely Tuesday morning/afternoon into SCA with
sustained 20 knot northerlies.
Will need to keep an eye on the swell from TD 16 soon to become Nate
as this could have some impacts Sunday and Monday with swell.
45
TROPICAL...
There is not terribly much to add to the discussion that hasn`t
already been mentioned in regards to TD 16. The most important
takeaway at this time is to continue to monitor for the latest
information from the NHC, and to the latest for us, as to what
impacts this will have on our area. These impacts may not be
direct storm impacts, but rather indirect, such as issues on Gulf
facing beaches due to higher swells from the storm. The precise
track of the storm will also strongly influence potential for rain
late this weekend.
The storm also serves as a reminder that hurricane season does not
end until November 30, and it is important to replenish supplies
in your hurricane kit.
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 87 69 89 66 89 / 0 0 0 0 0
Houston (IAH) 87 70 89 67 87 / 0 0 0 0 0
Galveston (GLS) 87 78 86 77 86 / 10 10 10 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION until 2 AM CDT Thursday for
the following zones: Coastal waters from Freeport to the
Matagorda Ship Channel out 20 NM...Coastal waters from High
Island to Freeport out 20 NM.
Small Craft Advisory until 10 AM CDT Thursday for the following
zones: Waters from Freeport to the Matagorda Ship Channel
from 20 to 60 NM...Waters from High Island to Freeport from
20 to 60 NM.
&&
$$
Discussion...43
Area Forecast Discussion
National Weather Service Wichita KS
718 PM CDT Wed Oct 4 2017
.UPDATE...
Issued at 718 PM CDT Wed Oct 4 2017
Tonight-Thu Morning:
Dense fog is spreading SE & 7 PM had spread into Nrn Barton & most
of Rice counties. As such, a Dense Fog Advisory has been issued
for the 5 northwestern-most counties until 10 AM CDT Thu.
&&
.SHORT TERM...(This evening through Saturday night)
Issued at 257 PM CDT Wed Oct 4 2017
A shortwave trough drifting over the central plains has resulted in
widespread showers and thunderstorms across much of the forecast
area. As the subtle trough axis passes, we should see a period of
subsidence in it`s wake. This may persist into much of the evening
hours and perhaps much of the night before another round of showers
and storms develop toward morning on Thursday with continued mid lvl
waa/moisture transport within a very moist pbl with pwats around 2
inches and layer warm cloud depths exceeding 4000 meters. The
surface front is still progged to return north on Thursday although
the RAP is slower on the return when compared to the GFS and NAM. As
the front returns north, there may be a potential for some
advection fog with very moist air poised just south of the front.
A more significant mid/upper trough will move into the Rockies on
Friday. Diffluent mid/upper flow will develop downstream across the
central plains where a cold front will arrive late in the day and
into the evening hours. This front will become a focus for deep
moist convection. Moderate instability and strong deep layer shear
will bring the potential for a line of severe storms with damaging
winds and some large hail. Heavy rain may aggravate any potential
flooding problems.
Saturday...a stable post-frontal regime is anticipated as much drier
continental air overspreads the area in the wake of the front with
seasonable highs in the 70s. There may be a few lingering showers
early in the period, however dry weather is expected to prevail by
afternoon.
.LONG TERM...(Sunday through Wednesday)
Issued at 257 PM CDT Wed Oct 4 2017
A mean mid/upper trough is progged across the central
Conus as the beginning of the period with a fropa on Monday bringing
low probabilities for precipitation and another surge of cooler air.
As we move toward the middle of the week, seasonably cool
temperatures and drier air is anticipated.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 718 PM CDT Wed Oct 4 2017
Most, if not all, of Central & South-Central KS will be shrouded in
LIFR cigs & vsbys throughout the night & until ~15Z Thu. At 00Z, SE
KS was in MVFR cig status but deterioration is likely late this eve
with LIFR cigs possible ~05Z. Cigs & vsbys should improve to MVFR
in all areas ~15Z Thu as lwr-deck flow becomes sly & increases.
&&
.HYDROLOGY...
Issued at 257 PM CDT Wed Oct 4 2017
With the potential for additional rounds of heavy rain Thursday
night and again along the front on Friday, a flood watch will been
issued for much of central KS where some pockets of heavy rain
have already occurred. This watch will be in effect from Thursday
morning through Friday night.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 65 78 66 83 / 40 50 50 50
Hutchinson 62 78 66 81 / 50 60 70 70
Newton 62 77 65 80 / 50 60 60 60
ElDorado 65 77 66 82 / 50 50 50 40
Winfield-KWLD 68 78 67 83 / 40 50 30 30
Russell 58 78 63 74 / 50 50 90 70
Great Bend 59 78 64 75 / 50 50 80 60
Salina 61 79 67 78 / 70 80 90 70
McPherson 61 78 66 79 / 50 60 80 70
Coffeyville 67 78 66 83 / 50 40 20 10
Chanute 67 77 66 82 / 50 60 30 30
Iola 67 77 66 82 / 60 60 40 30
Parsons-KPPF 68 78 66 82 / 50 50 20 20
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
Flood Watch from 7 AM CDT Thursday through Saturday morning for
KSZ032-033-047>050.
Dense Fog Advisory until 10 AM CDT Thursday for KSZ032-033-047-
048-050.
&&
$$
UPDATE...EPS
SHORT TERM...MWM
LONG TERM...MWM
AVIATION...EPS
HYDROLOGY...MWM
Area Forecast Discussion
National Weather Service Lincoln IL
854 PM CDT Wed Oct 4 2017
.UPDATE...
Issued at 854 PM CDT Wed Oct 4 2017
Showers are steadily advancing into central Illinois from the SW,
as a shortwave progresses to the east along the stalling out cold
front. Soundings show limited instability available for this wave,
and no lightning is being reported near our area, not even cloud
flashes. The showers are arriving slightly faster than the high
resolution models indicated a couple hours ago, and we have
updated the PoPs/Weather to reflect the expected short term
trends. The precip shield should advance eastward toward Indiana
the rest of the night, with northern areas seeing less precip
amounts, but still light rain/drizzle are poised to affect areas
north of I-74. HRRR is showing additional shower development later
tonight farther north toward Peoria, which will push toward
Bloomington after sunrise.
Low temps will be held up by clouds and precip, with mid 50s north
and mid 60s south. Only minor changes needed this evening to
hourly temps/dewpoints.
The latest forecast info is already available.
&&
.SHORT TERM...(This evening through Thursday)
ISSUED AT 301 PM CDT Wed Oct 4 2017
A relative lull in precipitation chances will take place tonight
into early Thursday morning with a cold front stalled out between I-
72 and I-70, then precipitation will increase Thursday as southerly
flow across the area pushes the front northward as a warm front.
Expecting enough instability for isolated thunderstorms by Thursday
afternoon.
With the frontal boundary stalled in the area tonight we should see
patchy fog forming in the general vicinity, which is currently
depicted by several models.
Lows tonight should range from 55 to 60 north of I-74 to the mid 60s
south of I-70. Areas between I-72 and I-70 may see high temperatures
increase a few degrees to around 80 due to the northward migration
of the front through the day, but otherwise temperatures will be
roughly the same as Wednesday with highs from the lower and mid 70s
north of I-72 and the lower 80s south of I-70.
.LONG TERM...(Thursday night through Wednesday)
ISSUED AT 301 PM CDT Wed Oct 4 2017
Thursday night, precipitation rates should increase especially west
of the Illinois River as a low level jet strengthens from the
southern Plains into the mid-Mississippi Valley region. This area of
precipitation should shift eastward Friday especially through areas
north of I-72 and have likely to categorical PoPs in this area. A
strong upper level wave arrives Saturday bringing another focused
period of showers and thunderstorms. Precipitation totals from
tonight into Saturday night still look to potentially exceed 2
inches northwest of the Illinois River, but decrease down to around
1 inch along I-72 and less than 1/2 inch along and south of I-70.
Warmer than normal temperatures look to prevail through much of the
next week before a cooler air mass is indicated starting around the
middle of next week. Until then, models are very inconsistent
handling a potential trough for early next week. Have a chance of
precipitation to account for this potential system, but uncertainty
in this time period remains high.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 659 PM CDT Wed Oct 4 2017
The stalled frontal boundary, roughly between I-70 and I-72, will
keep winds light and variable overnight. A wave of energy
advancing along the front this evening will cause showers to
expand in coverage from SW to NE. High resolution guidance and
forecast soundings support IFR or LIFR clouds for our southern
terminals of SPI and DEC, closer to the front. VFR conditions are
expected for the northern terminals of PIA, BMI, and possibly CMI
later this evening as mixing increases with the arrival of
showers.
MVFR fog appears poised to develop, after a day of light
rain/drizzle across central Illinois, and little change in airmass
overnight. The fog could drop to IFR later tonight, but have not
included those conditions yet.
Some improvement to VFR is projected for tomorrow afternoon, with
showers and even a few thunderstorms possible. Confidence in
thunder is low, with marginally unstable conditions expected.
Winds will vary widely from north to south across our area, due
to the location of the stalled front. Wind speeds should remain
light throughout the next 24 hours.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Shimon
SHORT TERM...37
LONG TERM...37
AVIATION...Shimon
Area Forecast Discussion
National Weather Service Indianapolis IN
1141 PM EDT Wed Oct 4 2017
.UPDATE...
The AVIATION Section has been updated below.
&&
.SYNOPSIS...
Issued at 334 PM EDT Wed Oct 4 2017
A frontal boundary will settle into the region and stall
overnight, before returning back northward as a warm front later
in the week as the accompanying cold front pushes toward the area.
This will bring multiple opportunities for showers and perhaps a
rumble of thunder to the area at times through the weekend and
into early next week.
&&
.NEAR TERM /Overnight/...
Issued at 942 PM EDT Wed Oct 4 2017
Surface analysis late this evening shows low pressure near St.
Louis. Water vapor shows a short wave associated with this feature
along with abundant cloud cover ahead of the low. Radar mosaics
show showers over western Illinois and eastern Missouri...pushing
eastward. Models suggest the eastward propagation of the rain
showers across Central Indiana overnight. Forecast soundings and
Time heights also show deep saturation arriving by 10Z-12Z. Dew
points across the area were in the middle 60s...plenty of moisture
available for early October. Thus have trended pops higher
overnight as the short wave and associated precip shield should
reach Central Indiana for the morning rush hours. Given the
expected increase in cloud cover trended overnight low at or above
the forecast builder blend...expected across the far east where
some mostly clear skies allowed temperatures to fall rather
quickly.
&&
.SHORT TERM /Thursday through Saturday/...
Issued at 334 PM EDT Wed Oct 4 2017
Will carry chances again tomorrow as late night impulse continues
to impact the area into the morning hours. Chances will again be
lesser later in the day but with some potential for warming have
added isolated thunder to the afternoon hours. Thursday night and
Friday focus will be more towards the north nearest the boundary
and another upper level wave with a strong gradient of pops over
the area. Convective indices suggest our next reasonable chance
for a few rumbles of thunder will come Saturday afternoon as the
cold front approaches.
Consensus temperatures appeared reasonable throughout. Should see
highs climb a bit back into the 80s by Saturday as we get into the
warm sector. Lows through the period will generally remain in the
lower 60s as moist air remains in place across the area.
&&
.LONG TERM /Discussion for Saturday night through Wednesday/...
Issued at 235 PM EDT Wed Oct 4 2017
Much of the extended period remain unsettled with periods of
showers and storms until a strong cold front arrives Wednesday.
Model differences are not huge and a blend is a fair compromise.
Temperatures will remain above normal until much cooler and below
normal readings arrive Wednesday.
The period starts with a surface pressure trough settling southeast
across the area with showers and storms still possible across our
southern counties Saturday night.
Sunday into Monday, a bit of model variance here but all trend to
pulling tropical moisture a bit further north into the Ohio
Valley. Rain chances still appear best in our southern counties
but chances up to I-70 corridor not out of the question. This wave
exits the area Monday night.
Tuesday and Wednesday...models agree in bringing full latitude trough
across nations midsection with fairly decent shower and storm
chances here. Model differences are in how much, if any, a second
surge of tropical moisture gets drawn into our area ahead of the
approaching trough. End result of differences likely to translate
into total precipitation amounts with this final surge of wet
weather before strong drying and cool temperatures settle in.
With a continuation of weak upper ridging or zonal flow for our
area, no real surge of cool weather is expected before the large
trough arrival Wednesday. Thus blend of well above normal max and
min temperatures through Tuesday looks good followed by below
normal Wednesday.
&&
.AVIATION /Discussion for the 050600Z Tafs/...
Issued at 1141 PM EDT Wed Oct 4 2017
VFR Conditions are expected to deteriorate to MVFR overnight.
Showers and lower cigs associated with Low Pressure over Missouri
will push east to central Indiana in the next 3-6 hours. Forecast
soundings and Time height sections continue to show a saturated
column near 12Z with continuing through the morning hours as the
low and associated short wave pass across Indiana. HRRR is also in
agreement for showers across the area near 12Z. Best lift and
moisture is lost after 18Z and will expect some improvement in
conditions at that time.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Nield
NEAR TERM...PUMA
SHORT TERM...Nield
LONG TERM...Tucek
AVIATION...JP