Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/12/16
Area Forecast Discussion
National Weather Service Columbia SC
1023 PM EST Fri Nov 11 2016
.SYNOPSIS...
An approaching cold front will move through the forecast area
overnight. Little moisture will be associated with the front. The
pressure ridge behind the front will extend through the Ohio River
Valley Saturday. Weak low pressure will develop just off the
Georgia and South Carolina coast Sunday. The low will lift
northeast of the area Monday. Most of the moisture associated with
the low will stay east of the forecast area.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
A fire danger statement remains in effect due to burning ban over
portions of the area.
The cold front will push south of the forecast area overnight.
Winds are already shifting from the northwest to the northeast
behind the front. Air quality relative to smoke should improve
with the wind trajectory behind the front. Wind will be stronger
over area lakes overnight because of increased mixing associated
with the relatively warm water temperatures. The HRRR suggested
gusts around 25 knots. Will continue the Lake Wind Advisory. The
wind should help hold up temperatures tonight despite the cold
advection. The temperature guidance was consistent with lows in
the lower 40s north to upper 40s south.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
It will be dry behind the cold front Saturday and Saturday night.
The NAM BUFKIT momentum transfer tool suggested breezy conditions
Saturday especially on area lakes where increased mixing will
occur associated with the relatively warm water early. Believe
gusts near 25 knots will occur supporting a continued Lake Wind
Advisory. Followed the guidance consensus for the temperature
forecast. Expect highs near 60 north to the middle 60s south. The
NAM and GFS MOS indicate relative humidity higher compared to the
previous day. Expect minimum humidity 30 to 35 percent.
There will be diminished wind Saturday night with the surface
pressure ridge closer to the area. Strong net radiational cooling
will occur but it may be limited by some mid-level cloudiness late
ahead of the next approaching shortwave trough. The temperature
guidance has trended upward in south and central sections but has
been more consistent in the north. Followed a guidance consensus and
forecasted lows near 30 north and in the middle and upper 30s
central and south. Confidence was high enough to post a freeze watch
in the north.
The models develop low pressure off the Georgia and South Carolina
coast Sunday in response to the upper trough moving into the area.
This low is depicted lifting farther northeast of the area Monday.
Deepest moisture and lift may occur late Sunday and Monday morning.
The models display a tight moisture gradient across the area with
deepest moisture east. The gradient diminishes forecast confidence.
Followed the lower pop guidance based on previous runs indicating
less moisture and the initial very dry environment. Followed the
guidance for the temperature forecast.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
The GFS and ECMWF indicate a dry pattern during the medium-range
period. The models show ridging over the area in the wake of low
pressure moving toward the Mid-Atlantic region Tuesday. A cold
front will little moisture is forecast Wednesday. High pressure
behind this front should dominate Thursday and Friday. The GFS and
ECMWF MOS plus GFS ensemble mean support pops less than or equal
to 20 percent through the period. The MOS has near or a little
above temperatures during the period.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
A cold front will push south through the area overnight which
should help clear out some of the smoke related VSBY restrictions
we have been observing. MVFR vsbys at OGB/AGS/DNL to start the
forecast with smoke settling beneath a developing inversion with
some possibility of IFR vsbys at AGS through 04z or so. The front
will push through during the 04z-06z time frame with winds
shifting northerly and picking up to around 8 knots which should
improve vsbys back to VFR all terminals by 06z.
Northeasterly winds will persist through the day Saturday around
10 to 12 knots with some gusts to 20 knots possible due to strong
mixing taking place. The wind direction should prevent any
additional smoke issues on Saturday.
EXTENDED AVIATION OUTLOOK...Some possibilities of MVFR CIGS and
light precipitation Sunday night/Monday morning. By middle of
next week, reduced visibilities in smoke could return.
&&
.FIRE WEATHER...
Fire Danger will remain elevated. Wind and relative humidity
values support an increased risk of wildfire. A fire danger
statement has been issued in coordination with the USDA Forest
Service and SC Forestry Commission. The SC Forestry Commission has
also expanded the burn ban to include the western Midlands and
Lexington/Richland counties.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...Lake Wind Advisory until 3 PM EST Saturday for GAZ040-063>065-
077.
SC...Lake Wind Advisory until 3 PM EST Saturday for SCZ015-016-018-
020>022-025>031-035>038-041.
Freeze Watch from late Saturday night through Sunday morning
for SCZ015-016-020>022.
&&
$$
Area Forecast Discussion...UPDATED
National Weather Service Corpus Christi TX
940 AM CST Sat Nov 12 2016
.DISCUSSION...Mid and high level cloudiness will continue to
increase over the region through the day. Lowered high temps 1-2
degrees over the area for this afternoon. Water vapor imagery
shows the mid to upper level low is slowly moving northeast into
West Texas while the upper level jet stream was over northern
Mexico into central Texas. Right entrance region of the upper jet
will provide lift over the area tonight. GFS model indicated
increasing isentropic lift in the 305-310K layer and latest HRRR
and Texas Tech WRF models show areas of light stratiform rain
increasing in coverage from Deep South Texas into the area by this
evening. Increased PoPs to 30 percent for southern portions of the
area for this evening and continuing into the overnight and
inserted slight chance for the northern counties this evening.
&&
.PREVIOUS DISCUSSION... /Issued 532 AM CST Sat Nov 12 2016/
DISCUSSION...
See Aviation discussion for 12Z TAFS.
AVIATION...
Could have some brief MVFR conditions at KLRD after midnight and
before the end of the forecast, but too late in the forecast to
warrant a mention with lack of uncertainty. Rest of the locations
should be VFR.
Based on GFS time- height plots, did include some -RA for all
terminals, starting around 19Z at KLRD, then a couple hours later
terminals farther east as best lift pushes east and atmosphere
gets a bit more saturated. Will begin ending the rain from west to
east around 13/05Z at KLRD and just having a PROB30 after 05Z at
KCRP and KALI. No rain mentioned after 09Z at KVCT. Please
note...this does not mean it will always be raining at the
terminals this afternoon and evening, but there should be enough
light rain or sprinkles to warrant it in the forecast.
Concerning winds...not too much of a concern with northerly winds
less than 11 knots and in some areas (like KLRD) could be
relatively light and variable for a time especially after sunset.
&&
.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi 77 63 75 62 79 / 20 30 30 10 10
Victoria 78 57 74 55 78 / 10 20 20 10 10
Laredo 74 61 74 59 79 / 20 30 20 10 10
Alice 77 60 75 58 80 / 20 30 30 10 10
Rockport 76 63 74 64 77 / 10 20 30 10 10
Cotulla 76 60 76 56 80 / 20 20 10 10 10
Kingsville 77 60 74 59 79 / 20 30 30 10 10
Navy Corpus 75 65 73 65 78 / 20 30 30 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
TMT/89...SHORT TERM
Area Forecast Discussion
National Weather Service Bismarck ND
317 PM CST Sat Nov 12 2016
.SHORT TERM...(This evening through Sunday)
Issued at 316 PM CST Sat Nov 12 2016
Tonight an approaching cold front, which will bring modified
Pacific air, will move through the region dry. The winds will
shift to the west to northwest with good mixing. lows will be in
the mid 30s to lower 40s.
Northwest winds will pick up to 15 to 30 mph on Sunday as cooler air
continues to move into the region behind the cold front. Look for
highs from the lower 50s northwest to mid 60s south central and
southeast. Matched the HRRR forecast minimum relative humidity for
Sunday afternoon...as well as the consmos for winds...instead of
going strictly by blended models. These models did well for Saturday
afternoon`s conditions.
.LONG TERM...(Sunday night through Saturday)
Issued at 316 PM CST Sat Nov 12 2016
The main message for the long term period is a storm system
that may affect our area Thursday and Friday.
Global models continue to forecast a trend to more normal or even
below normal temperatures in the 5 to 7 day period. A wet period
also looks increasingly likely for the end of the week. While it
would not be unusual to expect snow for the third week of November,
the unusually mild first half of the month will make any change seem
abrupt. Today`s 12z run of the ECMWF is developing the low farther
south into the central plains, while the GFS is a bit farther north.
The Monday through Wednesday period will see a moderate to strong
progressive h500 flow bringing a series of fast moving waves
with little moisture. Several frontal passages will bring some
temperatures swings but little precipitation. Temperatures will
still be mild with highs generally in the 50s to around 60 Monday
and Tuesday...with 40s and 50s on Wednesday as the upper ridge moves
east and the flow becomes southwest.
Thursday and Friday are expected bring a significant change to the
current weather pattern. Its likely to be cooler and wetter. While
details are far from certain there will be a chance for rain and snow
and gusty winds. Those planning travel will want to keep updated.
Moderating conditions on Saturday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1221 PM CST Sat Nov 12 2016
Vfr cigs/vsbys through the TAF period.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JV
LONG TERM...JV
AVIATION...JJS
Area Forecast Discussion
National Weather Service Corpus Christi TX
325 PM CST Sat Nov 12 2016
.SHORT TERM (Tonight through Sunday night)...
Satellite imagery shows the mid/upper level low over the Texas
Panhandle moving slowly eastward. The low will move into Oklahoma
by Sunday morning and through the Ozarks Sunday evening. Satellite
imagery also shows jet stream from north central Mexico into
central Texas. There also seems to be moisture tap from an area of
convection off the southwest coast of Mexico. The upper level jet
streak will move to the northeast tonight into Sunday as the upper
low moves eastward. South Texas will be in the right entrance
region of the upper jet and provide atmospheric lift as moisture
gradually increases from the south. Isentropic upglide was
indicated by the models in the 305-310K layer. Latest HRRR and
Texas Tech WRF models continue to show an increase in areal
coverage of stratiform rain tonight and especially on Sunday.
Went with chance PoPs across the southern portion of the area for
tonight and slight chance north. Increased PoPs closer to guidance
values for Sunday. Not confident enough in measureable amounts to
go with MAV likely PoPs at this point however. Upper jet will move
to the east and lift associated with it will exit also. Rain
chances will diminish by Sunday evening.
&&
.LONG TERM (Monday through Saturday)...
Still expecting some rather dense cirrus Monday morning but the
H25 jet shifting southeast of the area...and significantly drier air
in the mid levels...will result in clearing skies during the day.
Mid level trough and weak surface front are prog to push SE across
the CWA Monday night with little impacts expected to the area. Weak
W/NW flow in the post FROPA airmass should result in a cool
night Monday night as a 1021mb sfc high tries to build into the
region. Despite weak north flow on Tuesday...very dry conditions in
all levels of the atmosphere should result in rapid warming with max
temps in the 80s nearly areawide. Strengthening mid level ridging
and continued dry airmass on Wednesday/Thursday will result in
unseasonably warm conditions with near record highs possible.
Powerful lee-side cyclogenesis out of the Rockies on Thursday will
aid in developing breezy to windy conditions across the CWA. This
low is prog to quickly eject east on Friday and send a strong cold
front south towards the CWA. Both the GFS and ECMWF hint at the
front quickly sweeping across S TX either Friday evening or Friday
Night. A thin band of showers and isolated thunderstorms may develop
along the immediate front...primarily across the Victoria area
southward along the barrier islands /and offshore/ where moisture
depth will be the greatest. Strong and elongated surface high
pressure ridge then builds into the region over the weekend with
noticeably cooler conditions.
&&
.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi 63 74 61 82 58 / 30 40 10 10 0
Victoria 59 74 57 81 56 / 20 30 10 0 0
Laredo 63 73 60 81 61 / 30 30 10 0 0
Alice 61 74 58 82 56 / 30 40 10 0 0
Rockport 64 74 63 78 60 / 20 40 10 10 0
Cotulla 60 75 57 82 57 / 20 20 10 0 0
Kingsville 62 75 59 81 56 / 30 40 10 10 0
Navy Corpus 65 73 64 78 62 / 30 50 10 10 0
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
TMT/89...SHORT TERM
RH/79...LONG TERM
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
345 PM EST Sat Nov 12 2016
.SHORT TERM...(This evening through Sunday night)
Issued at 345 PM EST SAT NOV 12 2016
19Z MSAS surface analysis indicating high pressure is centered
across central IL. This is leading to a N to NE flow across the
region and at times a few spots will gust to around 15 knots.
Temperatures have been cool across the region with highs so far in
the low to mid 50s. The dry air is also evident with dewpoints in
the low 20s for many spots. This dry air will of course keep the
wildfire risk going. This high pressure will continue to progress
SE into the region tonight and will crest across the region
overnight. The other big story here is the likely freezing
temperatures given the dry weather, cool afternoon highs, and
decoupling. The COOP MOS data did come in slightly warmer, but
still went with lower 20s in the colder valley locales given
afternoon dewpoints. This will likely put the growing season to
bed for all of eastern KY.
Sunday the surface high pressure will continue SE but becomes
broad overtime. There is some question if we can manage to see
more SE flow which could lead to more smoke across the area from
larger fires to the south. Right now it looks limited based on the
HRRR smoke product for both near surface and vertically integrated
smoke. Either way we are looking at another dry day, with RH in
the sub 25% range. Therefore wildfire risk will continue, however
the winds are not expected to be a factor given the high pressure
placement. A squeezed off upper low will be centered across the TN
Valley region and will slowly migrate ENE through the day. This
will bring some high to mid level clouds into the far south and
east.
These clouds will continue to move across the east and SE through
the night as the upper low progresses east. The dry air Sunday
afternoon will lead to the potential for a few cool spots, but
this may be more limited given the clouds.
.LONG TERM...(Monday through Saturday)
Issued at 300 PM EST SAT NOV 12 2016
Early in the period, a weak upper low will bring some clouds to the
area on Monday before it swings off to our east. Upper level ridging
will then build northeast into the eastern CONUS to end the work
week in response to a digging trough over the Rockies.
This will provide warming temperatures, with readings by Thursday
and Friday pushing the 70 degree mark. Southerly flow will also
increase across the area Thursday and especially on Friday but
moisture will be slow to return. This could set up a day or two of
breezy south to southwest winds in combination with low relative
humidity Thursday and Friday. Something to keep an eye on for sure
with the wildfire concerns across the area.
Our next weather maker remains on track to impact the area by Friday
night into Saturday as a deep trough swings northeast from the
Plains into the Great Lakes. Still some differences aloft in the
modeling which impacts how much rain is generated between the GFS
and ECMWF solutions with the frontal passage so kept PoPs in the 20
to 40 percent range for now.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1223 PM EST SAT NOV 12 2016
High pressure off to the NW will continue progress SE into the
region through the TAF period. This will lead to continued VFR
conditions through the period. We have seen NE winds around 5 to
10 knots, and a few gusts up to 15 knots not out of the
questions. However we will once again decouple through the
evening hours.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
Freeze Warning from 10 PM this evening to 10 AM EST Sunday for
KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120.
&&
$$
SHORT TERM...DJ
LONG TERM...ABE
AVIATION...DJ
Area Forecast Discussion
National Weather Service Raleigh NC
246 PM EST Sat Nov 12 2016
.SYNOPSIS...
Canadian high pressure will settle central NC tonight, then
gradually weaken during the day Sunday as a potent upper level
disturbance approaches from the west and an associated low
pressure system develops along the Carolina coast.
&&
.NEAR TERM /THROUGH SUNDAY/...
As of 245 PM Saturday...
A 1031mb surface high Over IL/IN continues to build across the
Central Appalachians and down into the Carolinas this afternoon.
Meanwhile, a shear axis stretching from the Lower Miss Valley
across NC/VA is shifting south across the Southeast US. A portion
of the aforementioned high should settle over NC tonight and
result in calm conditions over at least the northern half of the
area. The latest RAP indicates a weak MSLP gradient over eastern
NC that may not allow for complete decoupling of the boundary
layer, but the gradient looks weak enough for periods of calm and
strong radiational cooling. There is also some concern about high
clouds spreading in from the west-southwest after midnight as an
upper low begins to cut off south of Nashville, TN. However, RH
fields and forecast soundings suggest this will be very late and
may only impact the southern Piedmont/Coastal Plain. Guidance
basically ranges from 25-33 for overnight lows. Confidence is
highest in those mid to upper 20s north of US 64, where a hard
freeze is more likely. Observing sites across the south may only
hit 32 for an hour or two, but lows may be highly variable enough
for some areas to see upper 20s. Thus, the Freeze Warning is in
effect for all of central NC Sunday morning.
Cirrus will continue to pour in on Sunday and altostratus will
become thicker across the southern CWA during the afternoon, as
the aforementioned upper low begins to move east and tropospheric
deep warm advection increases. Some light rain may spreading in
from SC by mid/late afternoon, though the extremely dry airmass
over NC will take a little time to saturate, and the bulk of the
precipitation will come after 00z. Highs should reflect the
increasing/thickening cloud cover and onset of precip in the
south, with only lower 50s in the south and upper 50s in the
north.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
As of 140 PM Saturday...
Strong frontogenesis associated with the closed upper low moving
east out of the Tennessee Valley will produce enhanced lift along a
pronounced h85 warm frontal zone across the southern tier of central
NC Sunday night. Precipitable water increases in southeast flow into
the frontal zone towards 00z and expect precip to overspread the
south before midnight...will increase PoPs to likely and this is
probably low. The front lifts north rather quickly as the upper low
begins to lift northeast after crossing the mountains overnight.
Will shift the focus of likely PoPs to the northern tier and spread
more widely to the east where the inverted surface trof will provide
a second zone of enhanced rain. As the low lifts out...showers will
persist in the east Monday morning...tapering off over all but the
northeast by mid afternoon. Rainfall amounts should be fairly
significant and widespread...>1/4 inch across most of the area
and potentially >1/2 inch in the east.
Mins on Sunday night will be relatively mild...lower 40s. Highs
Monday are more problematic, with cooler highs...mid 50s...generally
across the north...and especially northeast where rain will persist
longer in the day. Highs across the south will only reach around 60
due to cloudiness...but an earlier breakout in the dry slot could
allow insolation to bump the numbers up a category or so. Expect
skies to progressively clear from the southwest Monday night...with
mostly clear skies after midnight. Weak cool air advection across
the northern tier will be offset by mixing...mins look to fall into
the upper 30s...perhaps some mid 30s in the northwest...with
lower 40s across the south.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 140 PM Saturday...
Dry conditions are expected for the remainder of the week as the
upper trof across the eastern Conus translates offshore ahead of
progressive ridging which will be building east into the area
through the weekend. Highs will be mostly low and mid 60s Monday and
Tuesday...reinforced by a rather weak and dry cold front on
Wednesday with highs finally reaching the mid and upper 60s by
Friday and Saturday. A cold front will be moving into the area over
the weekend and should be accompanied by showers as we will see
moisture return as the upper ridge moves offshore, but the timing
could be as early as Saturday afternoon...or delayed until
Sunday...so will only introduce slight chance PoPs on Saturday
at this point.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
As of 1255 PM Saturday...
A few 15-20kt wind gusts continue between RWI and FAY, but these
will diminish this afternoon as high pressure continues to build in
from the north. Winds will become very light, if not calm
overnight, with clear skies or some high level clouds above 15k ft
moving in from the south by 12z. There is high confidence in VFR
conditions through 18Z Sunday.
Outlook: An area of low pressure will move along coastal NC Sunday
night and Monday, bringing widespread rain and a very good chance of
IFR or LIFR. There is also a chance of low level wind shear Sunday
night. Surface winds will be out of the northeast until the low
departs on Monday, when winds will turn to southwesterly and
conditions will begin to improve back to VFR. VFR conditions are
then expected for much of the remainder of the week.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
Freeze Warning from midnight tonight to 9 AM EST Sunday for
NCZ007>011-021>028-038>043-073>078-083>086-088-089.
&&
$$
SYNOPSIS...SMITH
NEAR TERM...SMITH
SHORT TERM...MLM
LONG TERM...MLM
AVIATION...SMITH