Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/20/18
Area Forecast Discussion
National Weather Service La Crosse WI
752 PM CDT Fri Oct 19 2018
.UPDATE...Saturday
Issued at 752 PM CDT Fri Oct 19 2018
Strong northwest winds of 15 to 25 mph with gusts to 45 mph are
expected Saturday morning across portions of southeast Minnesota
and northeast Iowa. It will be windy elsewhere too with gusts of
30 to 40 mph expected. With RAP forecast soundings continuing to
support a Wind Advisory over the open and unsheltered areas of
southeast Minnesota and northeast Iowa, have decided to issue a
Wind Advisory for these areas from 8 AM to 2 PM Saturday. The
worst winds look to be in the 9 am to noon timeframe.
&&
.SHORT TERM...(This evening through Saturday)
Issued at 222 PM CDT Fri Oct 19 2018
Main short-term fcst concerns are the strong NW winds and SHRA/SN
chances centered on Sat morning, much colder highs on Sat.
18z data analysis had a `cold` front from NW WI to NW IA, making
steady progress SE across the region early this afternoon. Rain well
ahead of this front now limited to eastern WI/northern IL. Generally
cloudy ahead of the front and partly cloudy behind it today. Not a
lot of cold air behind this front either, with temps in the eastern
Dakotas and western MN in the mid 50s to lower 60s, actually warmer
than those ahead of the front being held down by low clouds and the
areas of -RA this morning.
Model runs of 19.12z initialized well. Solutions offering a tight
consensus as one NW flow shortwave drops by this evening and second,
rather vigorous shortwave drops quickly across MN/WI Sat morning.
Short-term fcst confidence is generally good this cycle.
In the short-term, main impact of the shortwave to pass around 00z
this evening is to spread a round of low level cold advection across
the area and steepen the sfc to roughly 750mb lapse rates. 850mb
temps progged in the 0C to -7.5C range across the area by 12z
Sat. This ahead of the second vigorous shortwave. Given the steep
lower level lapse rates, the vigorous shortwave and an increase of
900-800mb moisture, some SHRA/SN expected to spread into/across
the area late tonight/Sat morning near/east of the 500mb jet axis
and shortwave track. This mainly across the WI portion of the fcst
area. Little in the way of rain/snow fall expected as any SHRA/SN
looking to only impact any one location for an hour or two, but
given the steep lapse rates, any stronger SHSN could drop vsbys
below 1/2 mile for a short time as they pass. Previous fcst cycles
had raised SHRA/SN to 50-70% along/east of the MS river centered
on Sat morning and will continue this trend. Boundary layer temps
looking to be in the 30s to near 40 Sat morning, with the SHRA/SN
mix and keep any minor snow amounts limited to NE of I-94.
Steep low level lapse rates to 750mb, strong low level cold
advection and deeper subsidence in negative PV advection behind the
shortwave spread across the area Sat morning. Strongest/deepest of
the mixing into the stronger winds aloft is for a couple hours just
behind the sfc-700mb trough axis during the early/mid morning
hours. Gradient sfc winds progged in the 25-30 mph range Sat
morning, but a short period of gust potential to 45 mph behind the
sfc trough/front. May yet need a wind advisory for portions of
the fcst area Sat morning, but per consensus with neighbors will
hold off on any advisory and defer to evening/mid crew. Did
continue to beef up winds/wind gusts centered on Sat morning as
previous fcst cycles had done. Gradient relaxes rather quickly
during the afternoon and winds to diminish after 18z Sat. With all
the LL cold advection and strong NW winds, the Sat high
temperature roller-coaster taking a 20F dip from those of today
looks on track.
.LONG TERM...(Saturday night through Friday)
Issued at 222 PM CDT Fri Oct 19 2018
Fairly quiet weather expected through much of the long term period
following the rain and snow on Saturday. Surface high pressure will
move southeastward across Iowa and into Missouri and southern
Illinois Saturday night, leading to low level ridging over the
forecast area. Tightening pressure gradient then during the day on
Sunday will lead to breezy winds once again, but this time out of
the south/southwest. This, along with plenty of sunshine, means a
slightly warmer day, with highs generally in the upper 40s to mid
50s, though some potential to get even warmer with good mixing
expected.
Another cold front will slide through on Monday, but still looking
like there won`t be enough moisture brought in ahead of it to lead
to precip chances. The forecast area will then remain in the
transition zone between upper level ridging across north-central
portions of the CONUS and upper level troughing across New England
for a few days. This will lead to dry weather with highs in the mid
40s to lower 50s through Wednesday. The next precip chances will
move in on Thursday with the approach of some shortwave energy from
the southwest. However, forecast confidence regarding these chances
remains low given large amount of time between now and then and
model differences. The 19.00Z ECMWF is much more aggressive with
northward moisture return compared to the 19.12Z GFS, and therefore
brings more widespread precip to the area for Thursday and Friday.
In contrast, the 19.12Z ECMWF keeps much of the area dry on Friday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 651 PM CDT Fri Oct 19 2018
Low level wind shear will be a concern tonight through around 10Z
before surface winds increase ahead of an approaching compact
trough. The trough will swing through the area during the morning
on Saturday brining rain and snow showers, mainly over Wisconsin. Brief
MVFR to IFR conditions are possible under any snow showers.
Also, winds will be rather strong Saturday morning with sustained
winds of 20 to 22 kts with gusts of 30 to 38 kts possible. These
winds will quickly diminish after 18Z, but remain gusty at times
through late afternoon.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...Wind Advisory from 8 AM to 2 PM CDT Saturday for MNZ086-087-094-
095.
IA...Wind Advisory from 8 AM to 2 PM CDT Saturday for IAZ008>010-018-
019-029-030.
&&
$$
UPDATE...Wetenkamp
SHORT TERM...RRS
LONG TERM....CJA
AVIATION...Wetenkamp
Area Forecast Discussion...UPDATED
National Weather Service Corpus Christi TX
1032 PM CDT Fri Oct 19 2018
.DISCUSSION...
No major changes needed to the forecast for the overnight period.
Showers have mostly waned and/or moved off to the northeast this
evening. However, latest HRRR runs indicate redevelopment over the
Gulf Waters with this activity possibly approaching the coast.
Some heavy downpours may accompany these showers and isolated
thunderstorms. Overnight lows in the 60s inland with low 70s
along the immediate coast look reasonable.
The Coastal Flood Advisory and High Risk of Rip Currents remain in
effect into Saturday morning. Tidal levels along the barrier
islands should reach 2 ft MSL during high tide over the next
couple of hours.
&&
.PREVIOUS DISCUSSION... /Issued 724 PM CDT Fri Oct 19 2018/
DISCUSSION...
Updated for 00z aviation.
AVIATION...
Poor flying conditions will continue through the taf period. Low
clouds should return at VCT over the next few hours as MVFR/IFR
ceilings prevail ALI/CRP/LRD. LIFR ceilings will also be possible
at times overnight into Saturday morning as well. Included some
VCSH remarks tonight through the mid morning hours as the threat
for intermittent light rain/showers continue. Winds through the
period will be out of the northwest to north, generally less than
12 knots.
PREVIOUS DISCUSSION... /Issued 402 PM CDT Fri Oct 19 2018/
LONG TERM (Sunday through Friday)...
The GFS ensemble mean suggest the development of a coastal trough
Sunday night/Monday, with would combine with copious moisture (GFS
deterministic) to generate scattered/numerous convection Sunday
night through Tuesday. The GFS ensemble mean depict a mean upper
trough west of Texas which suggests that a series of upper
disturbances will move across the region Wednesday-Friday and
contribute to additional precipitation.
Marine...
A coastal trough will lead to light and variable winds this evening.
A reinforcing high pressure system will begin moving into the area
Sat morning leading to a moderate offshore flow. The offshore flow
is expected to increase to advisory levels by Sat night.
Minor tidal overflow is expected tonight in response to persistent
long period swells. The tide levels have increased to around 1 foot
above normal, which will lead to levels reaching 2 feet above MSL
during high tide. Therefore, have issued a Coastal Flood Advisory
for tonight into Sat morning to capture the various high tides
overnight into Sat morning. The risk of rip currents will remain
high tonight as well.
SCA conditions expected Sunday/Monday due to strong northeast wind
owing to strengthening MSLP gradient associated with increasing
surface high pressure to the north, and the coastal trough
development. The persistent northeast wind trajectory should
contribute to elevated water levels along the coast, and thus
minor coastal flooding may occur again during the Sunday
night/Monday period.
&&
.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi 68 75 66 72 60 / 50 60 40 30 50
Victoria 66 73 62 71 56 / 60 50 20 10 20
Laredo 63 71 62 65 56 / 20 50 50 60 60
Alice 66 73 64 70 57 / 40 50 40 30 50
Rockport 69 77 67 73 61 / 60 60 30 20 40
Cotulla 64 71 61 67 55 / 20 50 40 30 50
Kingsville 67 74 66 72 60 / 40 60 50 40 50
Navy Corpus 71 76 70 74 64 / 60 70 40 40 50
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...Coastal Flood Advisory until 10 AM CDT Saturday For the
following zones: Aransas Islands...Calhoun Islands...
Coastal Aransas...Coastal Calhoun...Coastal Kleberg...
Coastal Nueces...Coastal Refugio...Coastal San Patricio...
Kleberg Islands...Nueces Islands.
High Rip Current Risk until 7 AM CDT Saturday For the following
zones: Aransas Islands...Calhoun Islands...Kleberg
Islands...Nueces Islands.
GM...None.
&&
$$
XX/99...SHORT TERM
Area Forecast Discussion
National Weather Service Quad Cities IA IL
917 PM CDT Fri Oct 19 2018
.UPDATE...
Issued at 907 PM CDT Fri Oct 19 2018
Opted to issue a wind advisory Saturday for portions of northeast
and east central IA where most favorable juxtaposition of strong
subsidence/isallobaric rises, cold air advection and boundary
layer mixing yields gust potential to 40 kts per RAP and NAM
soundings. Can`t rule out needing to add additional counties
over east central IA into northern IL given similar setup, but
a bit more uncertainty with cloud cover especially into northern
IL thus held off in this area for now. Elsewhere it will be windy
as well, but likely just below advisory criteria at this time with
gusts 30 mph to possibly near 40 mph.
Also, with evening update will be dropping lows tonight by 1-3
degrees in many locations per temp trends and clearing skies.
&&
.SYNOPSIS...
Issued at 230 PM CDT Fri Oct 19 2018
Scattered rain showers have moved east of the area and we`ve been
left with cool, cloudy, and breezy conditions. As of 2 PM,
temperatures were in the 50s across eastern Iowa and northwestern
Illinois.
&&
.SHORT TERM...(This Evening through Saturday)
ISSUED AT 230 PM CDT Fri Oct 19 2018
Saturday
A strong vorticity max and 135 kt upper jet will rotate through the
Western Great Lakes region, quickly dragging a cold front through
the area. 850mb temperatures are forecast to fall to -7 C.
Wind Potential:
The main sensible weather impact on Saturday will be strong NW
winds from mid morning through mid afternoon. Model isallobaric
plots show rises of 4mb/3 hrs behind the front so could have a 2-3
hr window with gusts near 40 mph. Efficient boundary layer mixing
in cold air advection, and strength of the winds at the top of
the boundary layer, corroborate the likelihood for gusts up to 40
mph. Current forecast is slightly below Wind Advisory criteria
(sustained 30 mph or gusts to 45+ mph), but it`s something we`ll
have to monitor and will let later shifts analyze new data before
making final call.
The windy conditions, coupled with afternoon relative humidity
between 30-50%, will increase the risk for wildfire starts in
cured agricultural fields. If a fire were to ignite, it would
spread rapidly in the strong winds. However, forecast wildfire
conditions are well below extreme thresholds so no need for a Red
Flag Warning.
Precipitation chances are low overall -- could have a few isolated
showers or areas of sprinkles. Uttech
.LONG TERM...(Saturday Night through Friday)
ISSUED AT 230 PM CDT Fri Oct 19 2018
Dry conditions with mainly below normal temperatures will prevail
through much of the extended forecast period.
Clear skies and nearly calm winds will allow for good radiational
cooling overnight Saturday night into Sunday, which will result in
temperatures dropping into the middle 20s to near 30 by Sunday
morning. Sunny days and clear nights will be common Sunday through
Wednesday. Highs will be in the 50s and low 60s through much of the
extended period, with a few upper 40s in portions of the NE CWA
Sunday. Lows will be in the 30s and lower 40s.
Surface high pressure will move off to the east Wednesday night and
more so on Thursday; with return flow developing across the area.
There remains low confidence; due to model disagreement and return
moisture availability; for some slight precipitation chances mainly
nudging into the SW and western part of the CWA for Wednesday night
into Thursday morning, with chance PoPs working into areas mainly
along and west of the MS River Thursday evening into Fri.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday Evening)
ISSUED AT 637 PM CDT Fri Oct 19 2018
Main concern will be with winds on Saturday. Expect a period
of strong NW winds 25-35 kts with gusts to around 40 kts from
mid morning through early afternoon before slowly diminishing.
Strongest winds appear to be favoring the DBQ and CID terminals.
Otherwise, VFR conditions to dominate. Isolated high based
instability showers are possible as well Saturday mid morning
through early afternoon, but don`t anticipate any impact to
terminals.
&&
.HYDROLOGY...
Issued at 1200 PM CDT Fri Oct 19 2018
Minor to major flooding continues on several rivers in eastern
Iowa and northwest Illinois. Little, if any, rainfall is expected
over the next 7 days. All tributary rivers will continue to
slowly fall.
Coralville Lake Reservoir is still near crest today near 710.9
feet. It will slowly fall over the next week, reaching 707 feet
late next week.
On the Mississippi River, routed flow from upstream is resulting
in rises; and at some locations minor flooding; from Dubuque to
Le Claire. From the Quad Cities to Muscatine, some rises will be
seen through the weekend, but levels will remain within the
Moderate Flood category. Downstream of Muscatine, this will
temporarily delay recessions. River levels will remain high into
next week.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Wind Advisory from 8 AM to 2 PM CDT Saturday for Benton-Buchanan-
Cedar-Clinton-Delaware-Dubuque-Iowa-Jackson-Johnson-Jones-
Linn.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...McClure
SYNOPSIS...Uttech
SHORT TERM...Uttech
LONG TERM...14
AVIATION...McClure
HYDROLOGY...14
Area Forecast Discussion
National Weather Service Wilmington OH
935 PM EDT Fri Oct 19 2018
.SYNOPSIS...
Showers will develop this evening into tonight ahead of an
upper disturbance traveling to the Ohio Valley from the west.
More showers and strong winds will accompany a vigorous cold
front on Saturday. Cool and dry weather will follow the cold
front for Sunday.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
No significant changes were made to the going forecast, with the
main purpose of the update to adjust PoPs -- with 100 percent
chances along and ahead of the main band of precipitation, which
has essentially developed as expected. Just ahead of this band,
there was a brief period of winds gusting to around 20 knots or
slightly higher, but in the heavier rain the gusts have (for
now) calmed down again. This will change overnight as the
pressure gradient tightens, with low-level moisture advection
continuing to lower the ceiling heights in the middle Ohio
Valley. At the same time, RAP forecasts indicate a sharp
gradient in theta-e at 700mb, roughly corresponding to the cut-
off of the deep-layer moisture and the heavier precipitation.
Behind this feature, as cooler and drier air works in aloft,
moisture will become more shallow and precipitation will become
more drizzly.
Previous discussion >
Showers developing along a swath of short wave energy and
associated weak surface trough will push across the area this
evening into the overnight hours. Driven by an 80 knot 500 mb
wind, bulk of showers will occur along and south of I-71 where
mid level forcing and low level moisture convergence coincide.
Rainfall amounts will range up to a quarter inch in southern
locations. We will see wind gusts over 20 mph overnight as the
pressure gradient tightens well ahead of a strong cold front
due to arrive on Saturday. Patchy drizzle may be experienced
later tonight as showers end. Strong mixing and cloud cover will
help keep lows up in the mid and upper 40s.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A relative lull in precip will occur early Saturday, before a
potent cold front arrives with widespread showers Saturday
afternoon and evening. With only weak instability in a rather
shallow layer, kept thunder our of the forecast.
As temperatures climb back into the 50s, strong winds are
indicated starting Saturday afternoon, continuing through
Saturday evening and into Saturday night. Tapping into 40+ knots
at 850 mb, gusts close to 40 knots are likely for a brief time
late Saturday afternoon. Will continue to mention strong wind
potential in the HWO, while later shifts may view fresh guidance
and issue wind headline if necessary.
Precip will be ending Saturday night as high pressure and
downward motion move in under a confluent flow aloft. As
temperatures fall to near freezing, a few snow flakes may be
observed near the end of the event as the colder temps advect
in on the strong northwest flow behind the front.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
A quiet, dry, and seasonable period is in store for the Ohio Valley
for this time frame.
Behind a cold front, Sunday will start out about 10 deg cooler than
normal - upper 40s to around 50. Monday will moderate nicely to near
normal with a good bit of sunshine and southwest flow advecting in
warmer air. High pressure will then build over the Upper Midwest and
keep the Ohio Valley in a cool surface flow that will marginally
hamper the direct heating from generally sunny skies. Expect mid 50s
to some upper 50s for the remainder of the forecast period, warmest
over Kentucky. Overnight lows will be warmest Monday night as the
southwest flow keeps up - lower 40s most locations. Outside of this,
they should be slightly below normal in the middle to upper 30s.
The next chance of rain occurs at the tail end of the forecast -
Thursday night/Friday as shortwave energy pushes east from a low in
the mid section of the country. European is progressive with the low
and has a much higher chance of showers for day 7 onwards, whereas
the GFS weakens the wave during this time and reinforces the trough
over the plains states. Split the difference on Thurs night/Friday
and have low chance pops with low confidence in the forecast at this
point in time. Remainder of the forecast seems pretty solid and
seasonable.
&&
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
Several concerns in the aviation forecast today, beginning with
rain showers moving through the region right now. These showers,
for the most part, are not expected to impact aviation
conditions. However, ceilings will gradually lower through the
overnight hours, with periods of IFR ceilings expected at all
TAF sites. These IFR ceilings should persist through early to
mid morning, eventually lifting to MVFR and then VFR levels by
the 16Z-18Z time frame.
WSW winds will continue through the overnight period, gradually
shifting to the west by morning. Sustained winds will increase
into the 10-15 knot range, and occasional gusts to around 20
knots are expected.
Winds will be even more of a concern on Saturday afternoon. Once
the winds switch to the northwest, they will increase into the
15-20 knot range, with gusts as high as 32-36 knots between 18Z
and 00Z. Another chance of showers will also occur late Saturday
afternoon into Saturday evening, but conditions should remain
VFR.
OUTLOOK...Gusty winds will continue into Saturday evening.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...Coniglio
NEAR TERM...Coniglio/Hatzos
SHORT TERM...Coniglio
LONG TERM...Franks
AVIATION...Hatzos
Area Forecast Discussion
National Weather Service Little Rock AR
637 PM CDT Fri Oct 19 2018
.AVIATION...
Large area of rain across the state continues to slowly push to
the south and east. Beginning to see precipitation come to an end
at KHRO and KBPK...with rain just about to start at KPBF. Through
the overnight hours ceilings will continue to lower to IFR and
even some LIFR conditions at KHRO/KBPK/KHOT/KADF while other
terminals are forecast to remain at MVFR conditions. Precipitation
will push south of the state by mid morning with VFR conditions
returning for much of the day on Saturday.
&&
.PREV DISCUSSION...(ISSUED 252 PM CDT Fri Oct 19 2018)
Short Term...Tonight thru Sunday...
The upper level pattern will become much more amplified across North
America during the short term. The flat ridge across the eastern
US is being flattened by an energetic trof dropping down from
Canada, which will put AR under a nwly flow aloft by the end of
the short term period.
Surface high pressure and a reinforcing wave of cold air will
move into the region by Saturday night into Sunday. This will drop
temps back into the 30s across the north on Saturday night, and
highs on Sunday will be back into the 50s in most areas.
One concern will be frost on Saturday night into Sunday morning.
Earlier it appeared that this would be more isolated in nature,
but I am thinking it will now be a bit more prevalent across the
north. I am expanding the patchy wording to cover a larger area
during this time frame, and am putting the mention of "areas" of
frost in some of the more cold prone areas.
As far as the present is concerned, the precip across the nwrn
portions of the state has been much slower to advance to the east
and southeast than earlier thought. RAP and HRRR pegged it pretty
well starting around 12-13Z runs this morning, showing it coming
in much later in most areas outside the NW. For tonight I have
gone with a blend of the RAP/HRRR on timing of precip spreading
across the state. By morning the precip will still be lingering
across the southeastern zones, but most other areas should see
clouds and rain chances decreasing overnight.
Long Term... Saturday Night through Friday...
A ridge of high pressure over the Midwest will amplify between
two areas of low pressure, one across the Desert Southwest and the
Northeast, and advance eastward over the state early next week.
This will keep northwesterly flow aloft, providing dry and cool
conditions for Arkansas. In fact, Monday morning will be the
chilliest day in the forecast, with lows in the mid to upper 30s
across northern and central portions of the state, and we could
see some patchy frost in those areas.
As we approach midweek, the aforementioned area of low pressure
across the Desert Southwest will begin to push east towards the
state. Model guidance disagrees slightly on the strength and
placement of the vort max, but overall expect rain chances to return
to the forecast as the shortwave trough and associated cold front
sweep through the area.
Temperatures will be mild through the period, with highs in the
upper 50s and 60s, and lows (aside from Monday) in the 40s and 50s.
&&
.LZK Watches/Warnings/Advisories...NONE.
&&
$$
Aviation...65
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
714 PM CDT Fri Oct 19 2018
.UPDATE...
Issued at 714 PM CDT Fri Oct 19 2018
After coordination with WFOs Des Moines and La Crosse, decided to
hoist a wind advisory for parts of south central MN Saturday
morning. It still looks rather marginal, but areas from Mankato
down to Albert Lea will be seeing the front move through late
enough where diurnal mixing will get added to the mix of steep
lapse rates from CAA and favorable isallobaric winds from post
frontal pressure rises to help increase wind speed potential.
There is potential this could be expanded further to cover much of
the MN MPX coverage area as well, since much of the area will see
near advisory winds for a few hours in the wake of the front.
&&
.SHORT TERM...(This evening through Saturday)
Issued at 230 PM CDT Fri Oct 19 2018
Roller coaster weather continues with colder temperatures, gusty
northwest winds and threat of rain/snow showers late tonight into
Saturday morning.
Strong drying indicated with current water valor imagery behind
initial cold front. Expect strong northwest winds to continue
through about sunset. Then will recharge with next front moving into
the area after 06z. Water vapor imagery showing the next short wave
rotating southeast over Saskatchewan with the developing Canadian
upper trough. This is progged into eastern MN by 12z Saturday. The
GFS and ECMWF have been fairly consistent with the possibility of
some shower activity with this feature as it moves through. We will
hold onto the likely PoP into west central WI later tonight with
some chance type PoPs into central MN with fropa. Thermal profiles
do become more favorable for changeover to wet snow with fropa. Will
continue to mention some light accumulation, less than an inch over
west central WI. If we can get organized north/south linear banded
snow showers, we certainly could see some higher accumulation`s.
Gusty northwest winds to 35-40kts possible with fropa later tonight
as strong low level CAA develops and gradient increases. We could
see near criteria winds into south central MN Saturday morning.
Opted to hold off on the headline for now, and let the overnight
shift take one more look at that potential. Clouds may linger
through much of the morning east, but expect sunshine most of the
afternoon with winds gradually diminishing with the approach of the
high pressure ridge from the Dakotas. Temperatures may steady out
late morning and rise a couple degrees in the afternoon with more
sunshine. High in the upper 30s to low 40s and wind chills in the
mid 20s will provide another below normal autumn day.
.LONG TERM...(Saturday night through Friday)
Issued at 230 PM CDT Fri Oct 19 2018
No significant changes to the forecast through next week. Continued
the trend of raising Sunday`s temperatures above guidance for the
reasons outlined in the previous discussion. Forecast soundings
show clear skies and westerly winds in the boundary layer. H850
temperatures will be 7 to 10C, and although we likely won`t mix deep
enough to tap into that air mass, it still serves a good proxy for
raising afternoon highs.
Another frontal boundary will pass through Sunday night bringing
northwest winds and cooler temperatures, with Mondays highs expected
to be in the mid 50s. Tuesday will be dry again as a surface high
pressure builds across the Upper Mississippi River Valley. This will
bring lighter winds, so that should keep temperature a bit cooler
than the previous day, with highs only in the upper 40s.
Looking ahead, mostly sunny skies will continue for Wednesday and
Thursday, but this could be the end of the recent string of dry
weather. The reason being, a powerful jet will crash onshore the
Pacific Northwest and cut right through the omega block that has
been in place over the central US. A pool of positive vorticity
advection on the poleward side of this jet will lead to rising air,
clouds, and precipitation starting Friday and lasting through the
weekend. At this point there is still considerable spread on how
this will evolve and to what degree cyclogenesis will commence.
However, it certainly appears that most locations will receive at
least some rainfall, with the potential for 0.5 to 1.0 inches or
more.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 654 PM CDT Fri Oct 19 2018
Watching cluster of convection dropping into northwest MN for our
next chance of precip. Convection is quite vigorous, with cool
cloud tops and even the occasional lightning flash. Current
trajectory would have it follow a path similar to what the HRRR
has into western WI. Given the strength of the wave, did add some
-shra to RNH/EAU to account for that coming through, with VCs for
MSP/STC/AXN. Upper low will be going into central WI Sat morning,
so we could see scattered rain/snow showers continuing into the
morning across western WI. Behind the secondary cold front, GFS
bufr soundings show some impressive gust potential through mid
morning, so did boost wind speeds/gusts above guidance through
the morning. Winds will be diminishing, along with skies clearing
in the afternoon. Expect cigs to remain VFR, save for a brief
MVFR in any heavier showers.
KMSP...Given strength of the convection moving into northwest MN,
can`t completely rule out getting a quick shower as the front
moves through between 7z and 10z. Strongest winds are expected
between 10z and 16z, when gusts to, or even a little above 35 kts
will be possible.
/OUTLOOK FOR KMSP/
Sun...VFR. Wind SW 15G25kt.
Mon...VFR. Wind NW 10G20kt.
Tue...VFR. Wind NW 5-10 kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...Wind Advisory from 8 AM to 2 PM CDT Saturday for MNZ083>085-092-
093.
&&
$$
UPDATE...MPG
SHORT TERM...DWE
LONG TERM...JRB
AVIATION...MPG
Area Forecast Discussion
National Weather Service Nashville TN
1031 PM CDT Fri Oct 19 2018
.UPDATE...
FOR 06Z AVIATION DISCUSSION.
&&
.DISCUSSION...
Mainly light rain continues to work its way into Middle Tennessee
ahead of an approaching cold front. HRRR has been handling the
precipitation well thus far and the current short-range forecast
lines up well with existing POP grids. Most of the evening and
overnight rain will be light, and won`t completely exit the mid
state until after 12Z. Will update the forecast later this
evening for wording, but no changes to the actual forecast grids
are planned at this time.
&&
.AVIATION...
06Z TAF DISCUSSION.
Light rain has overspread all airports tonight along with
VFR/MVFR cigs/visibility. IFR cigs now look unlikely except at
CSV. Rain will end from west to east between 09-14Z but MVFR cigs
will linger until late Saturday morning/early afternoon. Light
west winds will continue through Saturday morning but increase and
become quite gusty out of the northwest late Saturday, with gusts
over 25 knots possible.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION......08
AVIATION........Shamburger