Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/25/17
Area Forecast Discussion
National Weather Service La Crosse WI
623 PM CDT Wed May 24 2017
.SHORT TERM...(Tonight through Thursday Night)
Issued at 237 PM CDT Wed May 24 2017
Pesky closed low that has been responsible for the clouds and
scattered showers over the last couple days now centered over MO per
latest GOES Water Vapor/Visible loops/RAP 500mb analysis. Shower
activity has pretty much shut down and moved south of the area
closer to the low, but still plenty of stratus and perhaps a patch
or two of drizzle to contend with today. Clouds also holding
temperatures back with reading this afternoon in the 50s, or some 20
degrees below our normal highs for today.
For tonight the closed low finally budges east more into the Ohio
River Valley as a ridge of high pressure builds in from the Plains.
Clouds and areas of fog could become problematic tonight. Where
clouds do clear, fog will almost be a certainty late tonight into
Thursday morning. This looks most likely along and west of the
Mississippi River closer to the ridge axis. East of the river,
clouds look to hang on overnight limiting the extent of fog. Will
have to keep and eye on how dense this fog becomes along/west of the
Mississippi overnight into Thursday morning. Otherwise, plan on lows
tonight in the lower and middle 40s.
After some morning fog, mid-level ridge and surface warm air
advection will provide a nice Thursday for the area. Look for highs
topping off in the upper 60s to the lower 70s.
Increasing warm air advection/850-700mb moisture transport ahead of
a mid-level trough moving through the Northern Plains could produce
some elevated/high-based showers across the area Thursday night.
CAPE at this point looks very minimal, so will leave thunderstorm
mention out for now. Look for lows in the lower/middle 50s.
.LONG TERM...(Friday through Wednesday)
Issued at 237 PM CDT Wed May 24 2017
Friday/Friday evening will see a chance of showers/storms as a weak
mid-level trough/surface cold front pushes east across the area. NAM
builds a corridor of 1000-2000 J/kg across eastern MN/northwest WI
along the front but rapidly diminishes it with loss of heating
toward evening as it moves into our area. Therefore, severe threat
looks minimal at this time. Otherwise, temperatures pre-frontally
expected warm into the upper 60s to middle 70s.
A weak east/west frontal boundary hangs up across central southern
sections of the forecast area Saturday with weak mid-level
frontogenesis and incoming weak pv-advection. For this reason, will
carry a slight chance of showers in the morning and 20-40 pops in
the afternoon with daytime heating. Still warm though with highs
expected to be in the 70s.
For Sunday into Memorial Day...models in good agreement on dropping
a mid-level trough through the region from Canada. This will bring a
chance of showers and afternoon/early evening thunderstorms given
steepening lapse rates.
Tuesday looks like a return to cooler/showery weather a cyclonic
flow takes hold across the region. Plan on highs in the lower/middle
60s.
Latest ECMWF/GFS showing some differences for Wednesday with the GFS
building a ridge into the area while EC maintains cooler/cyclonic
flow and continued showers. Consensus has the day dry for now with
highs in the mid-upper 60s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 623 PM CDT Wed May 24 2017
Satellite imagery late this afternoon shows lots of clouds
covering a good share of the area, but there are some breaks in
the overcast. The concern becomes will the clouds or the breaks
win out overnight. A weak ridge of high pressure extends from
northeast Minnesota into eastern Nebraska with the clouds
extending into and through the ridge axis over Minnesota. This
ridge axis is expected to slide east and extend from northwest
Wisconsin into northern Missouri by 25.12Z. The 24.18Z NAM is
pretty pessimistic on the clouds remaining overnight as it keeps
the low level moisture high but looking at the forecast soundings,
it does thin out the moisture depth. The 24.21Z RAP is more
optimistic and suggest it will clear out overnight. For now, have
maintained forecast continuity and gone with the clearing
overnight, but have also hedged toward the NAM and not dropped the
sky coverage nearly as much as the previous forecast. This will
all have a big impact on whether or how much fog will form
overnight. If it does clear out, with all the moisture and light
winds, would expect to see fog form with IFR conditions for both
airports. Without the clearing, any fog would be minimal but
ceilings could come back down to MVFR. Again, have maintained
forecast continuity with fog forming and IFR conditions
developing. Expect this will burn off not long after sunrise
Thursday with VFR conditions the rest of the day.
&&
.HYDROLOGY...
Issued at 237 PM CDT Wed May 24 2017
Recent heavy rainfall will continue to cause minor flooding along
portions of the Mississippi River and also the Trempealeau River at
Dodge this week into early next week. Be sure to monitor river
levels closely if you have any plans or interests along these rivers.
You can access this information on our website at weather.gov/arx.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...04
HYDROLOGY....DAS
Area Forecast Discussion
National Weather Service Bismarck ND
956 PM CDT Wed May 24 2017
.UPDATE...
Issued at 945 PM CDT Wed May 24 2017
Update to blend in observed radar trends with the going forecast.
Thunderstorm threat is mostly focused to the southwest along a
nose of steeper mid-level lapse rates. Otherwise no major changes
to the forecast.
UPDATE Issued at 810 PM CDT Wed May 24 2017
Updated to expire Wind Advisory with surface winds diminishing to
below advisory criteria on recent observations.
UPDATE Issued at 703 PM CDT Wed May 24 2017
We increased PoPs along and west of the Highway 83 corridor with
this update to reflect the eastward-propagating line of showers
moving across western ND early this evening. The vast majority of
convection-allowing model guidance, including recent HRRR cycles,
is not as aggressive with the areal coverage of precipitation as
radar imagery suggests. An exception was the 18 UTC 3 km NAM, so
we weighted the evening precipitation forecast strongly to that
simulation. We maintained a chance of thunderstorms in the west
and south central too in respect to mid-level lapse rates near
7 C/km, though CAPE for parcels lifted above a dry boundary layer
is meager outside of far southwest ND early this evening.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 257 PM CDT Wed May 24 2017
Gusty southerly winds ahead of the surface trough and associated
cold front will continue through the afternoon, although they may
diminish far west as the center of the trough moves over. The
short term CAM models have been more excited about thunderstorms
even though the cape is barely there. Shear is plentiful and with
the current lightning in eastern Montana, will include a few
hours of thunderstorms west and then trail off thunder to just
the southwest this evening.
Without good instability cant seem to get too excited about rain
potential over the next 24 hours. Current consensus is between a
tenth of an inch and up to a quarter of an inch west and north.
By Thursday the trough will be east and the chances for
precipitation remain just along the northern boarder. Used the
highest guidance for wind speeds Thursday which gave a reasonably
breezy but not windy day with west to northwest winds. Highs
Thursday will range from the lower 60s southwest to lower 70s
James River Valley. Current greenup will again keep fire danger
below the high level even with the gusty winds.
.LONG TERM...(Thursday night through Wednesday)
Issued at 257 PM CDT Wed May 24 2017
The weekend is shaping up to be on the cool side with scattered
showers. The best chance for showers still looks like Saturday.
Global Models see a sharply curved shortwave trough rotating
around the upper low which may produce enhanced vertical motion
fields Saturday. Following this, the upper low circulates around
Ontario funneling several more shortwave troughs through the
Northern Plains in what could be a modestly active northwest flow
regime. This pattern often produces an active thunderstorm
pattern in early June. While the Forecast Blend guidance is
generally dry see some potential next week. However due to
uncertainty left the extended after Monday dry but something to
watch.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 945 PM CDT Wed May 24 2017
A band of showers will move across western ND this evening, and
through central ND between about 04 and 09 UTC. There`s also a
small chance of thunderstorms with this shower activity, but we
refrained from including even a VCTS in the 00 UTC TAFs since
confidence is low in their occurrence at any of the terminals.
Otherwise, gusty south winds will diminish this evening. Winds
will become westerly by Thursday afternoon and increase once more
with gusts to 30 kt behind a cold front.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AE
SHORT TERM...WAA
LONG TERM...WAA
AVIATION...CJS
Area Forecast Discussion
National Weather Service Charleston SC
947 PM EDT Wed May 24 2017
.SYNOPSIS...
A cold front will push over the Atlantic by early Thursday
morning. Large high pressure will build over the region through
Thursday and will linger through this weekend. A weak cold front
is expected to slow slide over the region on Tuesday.
&&
.NEAR TERM /THROUGH THURSDAY/...
On the evening update, we adjusted POPs in many areas to reflect
ongoing radar trends with minor adjustments to winds and sky
cover.
The cold front has recently moved through Macon GA and was
approaching east central GA. Ahead of the front, clusters of
convective rains remained low-topped and have tended to diminish
as they approach the coast where the air mass was more stable.
The final batch of showers and tstms right along the front has
had a bit of a flare-up recently as it moves into a region of
increased MUCAPES, however latest HRRR and RAP13 high resolution
progs show this instability will wane before moving into our
inland zones prior to midnight. Isolated to scattered showers
and a few tstms will persist for the next few hours, ending
from west to east overnight as the cold front moves through.
Since the deep layered environment still has 40-50 KT of bulk
shear, the risk of severe weather is non-zero, but extremely
low given the lack of significant instability. Skies will also
clear from west to east later tonight and with the passage of
the front, slightly cooler temps and drier air will be moving
in.
Thursday, high pressure is forecast to become centered near FL
and will ridge north across the CWA. WSW winds will see gusts
gradually strengthen shortly after sunrise. Conditions will
feature mostly sunny conditions with near zero PoPs. High temps
should range in the upper 70s. Breezy to windy conditions are
likely by afternoon with the passage of a strong mid level
vort and deeper mixing. We may need a Lake Wind Advisory if
model trends continue to show higher surface wind gusts.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
Thursday: The upper level trough axis will cross the forecast
area mid-day as stacked low pressure continues its trek
northeast into the mid-Atlantic region. Surface high pressure
will begin to spill back in from the south and Gulf of Mexico
behind the cold front as weak upper-level ridging slides slowly
east. This should result in primarily dry conditions Thursday,
but a shower or thunderstorm cannot be entirely ruled out. A
tight pressure gradient will exist across the region, leading to
elevated and gusty surface wind speeds. Temperatures look to be
slightly below normal, with highs just under 80 degrees most
locales and low temperatures averaging around 60 inland and
around 65 at the coast.
Friday: Surface high pressure will overspread the region under
weak ridging aloft, continuing a period of calm weather with
almost zero probability for precipitation and mostly sunny skies
anticipated. Near-normal temperatures are anticipated with
highs reaching the lower to mid-80s before cooling into the mid
to upper 60s overnight away from the coast.
Saturday: Strengthening trough aloft to the west will induce an
area of low pressure at the surface over the central US. The
associated cold front will begin a slow trek southeast towards
the forecast area. High pressure at the surface will persist
locally under a ridge aloft, and another dry day looks highly
probable under this scenario. Temperatures climb back above
normal, aided by subsidence and some compression in advance of
the front. Expect high temperatures to reach the lower 90s away
from the coast and upper 80s at the beaches, with low
temperatures only dropping to around 70.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A ridge over the East Coast combined with surface high pressure
will result in mostly dry weather through the remainder of the
weekend. The surface cold front will approach the area through
the first half of the week as the trough aloft slides east,
bringing the potential for another period of unsettled weather
Monday through Wednesday.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Occasional MVFR cigs and showers are expected at both terminals
through the evening ahead of a surface cold front. There are
small chances for brief IFR cigs and vsbys below 3 NM in heavier
showers. Risk for thunder is generally low. Marginal low level
wind shear is possible overnight but most of shear will be speed
shear off the surface inversion. Skies will clear for Thursday
but it will become breezy to windy with west winds in the 20 to
30 mph range at time, especially at KCHS.
Extended Aviation Outlook: Expect VFR conditions to prevail
into the weekend.
&&
.MARINE...
Tonight: A cold front is expected to sweep across eastern GA/SC
late, pushing over the marine zones early Thursday morning.
Gusty SW winds will continue across the marine zones. Gusts
could reach near gale levels across portions of AMZ374 and 350
late this evening. Wave heights will continue to build through
this evening, reaching 5-9 feet within 20 nm and possibly
reaching near 10 feet beyond 50 nm. Small Craft Advisories will
remain in place all waters.
Thursday through Sunday: Tight pressure gradient behind the
surface cold front will lead to elevated and gusty SW to WSW
winds and increasing seas. A Small Craft Advisory has been
hoisted for all zones Thursday, with conditions gradually
improving Friday into Saturday under high pressure.
&&
.TIDES/COASTAL FLOODING...
Evening high tide levels will trend higher each day as we
approach the new moon and perigee this Friday, though we expect
tides to remain just below Coastal Flood Advisory stage. The
current tide is close to 7 FT MLLW at high tide this evening.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Small Craft Advisory until midnight EDT tonight for AMZ330.
Small Craft Advisory until 8 PM EDT Thursday for AMZ352-354.
Small Craft Advisory until midnight EDT Thursday night for
AMZ350-374.
&&
$$
NEAR TERM...
SHORT TERM...JMC
LONG TERM...JMC
AVIATION...
MARINE...
TIDES/COASTAL FLOODING...
Area Forecast Discussion
National Weather Service Huntsville AL
903 PM CDT Wed May 24 2017
.NEAR TERM...(Tonight)
Issued at 903 PM CDT Wed May 24 2017
A rather highly amplified upper level pattern continued over and near
the greater North American domain. A feature influencing local
weather was an upper low approaching the Tennessee Valley from the
Mid South. Both GOES 13 and 16 imagery nicely show this mid/upper
low. 25/0000Z 500mb heights around this low were near 551 decameters,
which is pretty low for this time of year. This has resulted in very
steep mid level lapse rates, which has lead to short lived, isolated
thunderstorms within shower bands near and southeast of this upper
low.
Local and regional radar views indicated scattered to at times
numerous showers moving in a west to east manner across the forecast
area. The back edge of these showers were over Mississippi River
between NE Arkansas and around Greenville MS. A few lightning
strikes (most of them intercloud) have been accompanying this
activity, seen from local LMA and MRMS.
For the rest of the overnight, the above mentioned upper low will
continue moving a bit south of east across the forecast area. Output
from the HRRR indicated 1000/500 thickness values below 550
decameters as this system swings by, especially between midnight and
3 to 4 AM. Shower activity with this system per the HRRR and RAP
should end across our eastern areas before daybreak Thu, with the
new NAM a bit slower with the drying trend.
Update wise, stayed close to previous forecast trends/timing. Did
lower rain chances over our eastern areas late tonight more in line
with the drier high resolution guidance. Cooler surface temperatures
(lows falling into the lower 50s and the already cold air aloft
should lessen lightning development after 10 PM, as lapse rates aloft
moderate somewhat.
.SHORT TERM...(Thursday through Friday night)
Issued at 304 PM CDT Wed May 24 2017
Thursday will be another relatively cool day for late May, with
consensus highs only reaching the low-mid 70s (normals are 83). There
is still an outside chance of a shower in northeast Alabama, since a
last-gasp shortwave will round the southwest flank of the departing
low. However, with precipitable water values less than an inch over
that region, the forecast will be left dry. One more below-normal
night is expected Thursday night with highs falling to the mid 50s.
The cool spell will come to an abrupt end as abundant sunshine,
strong SW flow and subtle mid-level ridging all kick in Friday.
Highs should easily reach the mid-upper 80s, with a nudge just above
blended guidance. A cold front will begin a slow southward push late
Friday into Friday night, but it should not get close enough to the
Tennessee Valley to warrant including any PoPs in the forecast
through Friday night.
.LONG TERM...(Saturday through Tuesday)
Issued at 304 PM CDT Wed May 24 2017
The latest med range model output continues to show deep SW flow
prevailing from the Mexican Plateau to the Southeast and Ohio River
Valley on Saturday. Meanwhile, a surface warm front will be lifting
north on Saturday afternoon in response to an approaching mid-level
shortwave trough moving within the subtropical jet. This will occur
in conjunction with a polar jet trough rotating around a parent
upper low moving southeast over Corn belt and Great Lakes region.
That particular trough will become important for later in the
evening/overnight Saturday night.
For Saturday, scattered storms may occur as the warm front moves
north during the late morning into early afternoon. Plan view of
instability parameters are showing a moderate to high amount of
instability during the afternoon, but forecast soundings indicate
most of this is elevated due to an EML present likely from the fetch
off the Mexican Plateau. Because of this limiting factor, will keep
scattered storms in the forecast, but this activity could have even
less coverage than forecast. As the warm front moves north, the
aforementioned shortwave trough will be pivoting southeast towards
the MS River Valley with a trailing cold front. The ensuing
confluence of the flow aloft will act to increase geostrophic flow
across the MS/TN/OH river valleys for Saturday night. Upstream (NW
of here) deep convective initiation is expected to increase in
coverage and likely form into a MCS rapidly moving southeast towards
the TN Valley on Saturday night. Deep layer shear is around 40-50
kts especially after 7PM. Most unstable CAPE (2000-3000 J/kg) is
mostly in the elevated portions of the profile (within the hail
growth zone) which would heighten the potential for large hail along
with heavy rainfall once the profile becomes saturated. Though some
uncertainty exists on the trajectory of the MCS, it should spread a
cold pool across the TN Valley which may limit convective activity
during the day on Sunday. However, additional showers and storms
should develop along the trailing surface cold front that should
move over the region sometime late Sunday night into early Monday
morning.
The latest med range models runs do show a slower trend with the
cold front passage which is plausible with the bulk of the upper
level forcing with the trough associated with the parent upper low
removed further to the north. So, the precipitation may not
completely clear before sunrise on Monday morning and may affect
Memorial Day outdoor activities. The temperatures should be cooler
behind the front for both Monday and Tuesday. Dry conditions should
prevail on Tuesday as well.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 630 PM CDT Wed May 24 2017
Mainly VFR conditions should continue through TAF. That being said,
an area of showers and a few embedded thunderstorms will continue
moving in a west to east manner across the area this evening. CIG
and/or VIS values may briefly be reduced to MVFR, but chances of it
are too low to include in the TAF. Stayed with a timing of the shower
activity ending around 07Z at KMSL and 08Z at KHSV. VFR altitude
lower clouds should persist for the rest of the night and during Thu
AM. As the coldest air aloft moves east of the region, expect a
broken cloud deck to scatter in the early afternoon.
&&
.HUN WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
TN...NONE.
&&
$$
NEAR TERM...RSB
SHORT TERM...BCC
LONG TERM...SL.77
AVIATION...RSB
For more information please visit our website
at weather.gov/huntsville.
Area Forecast Discussion
National Weather Service Jackson MS
921 PM CDT Wed May 24 2017
.UPDATE...
Updated for evening discussion.
&&
.DISCUSSION...
A few left over showers are still moving through our north central
region this evening that is associated with surface low to our
northeast. The latest HRRR model run shows rain dissipated by the
early morning hours and dry and clear sky conditions will
prevail come sunrise. POPs were cleaned up to reflect those few
rain bands to our north, otherwise no changes were necessary with
the latest forecast update. /12/
Prior discussion below:
Tonight through Thursday...
A deep cold core closed mid/upper-level low is progged to move from
the middle Mississippi River Valley to Ohio by Thursday morning with
the associated surface low also moving off to our northeast into the
Great Lakes region. With the loss of daytime heating and the low
pulling away from the area any lingering shower activity should
quickly dissipate late this afternoon and early evening after
sunset. Cloud cover will also dissipate from west to east and winds
should relax as the surface pressure gradient weakens. The light to
calm winds combined with clearing skies and highly anomalous low
500mb heights will set the stage for near record low temperatures
tonight under nearly ideal radiational cooling conditions with a
much cooler and drier airmass in place. Overnight low temps will
range from the upper 40s to low 50s. For Thursday, temperatures
will begin to rebound under sunny skies as flow becomes more zonal
and shortwave ridging builds into the western portions of the
ArkLaMiss. While temperatures will return to the upper 70s and low
80s they will still be around 5-7 degrees below average for this
time of year. /TW/
Thursday night through Wednesday...
As upper level ridging continues to pass through the middle of
the country, a surface high will cross from west to east over the
northern Gulf of Mexico. Dry and more seasonal weather is
expected over the ArkLaMiss on Friday and heading into the
weekend. Once the surface high settles near the FL peninsula on
Saturday, it will aid in blocking the next system from the north.
The discrepancy in the timing of the models exists even greater
today than that of yesterday. The GFS originates the low much
further north near the Great Lakes and holds the front off to the
north on Saturday and releases it southward into the ArkLaMiss on
Sunday. The latest Euro shows the low developing in the Arkansas-
Red River basin and tracks it into the Mid-Mississippi Valley on
Saturday. The front will slide through the CWA on Sunday and bring
showers and storms. There is plenty of instability and there are
decent lapse rates with this system. The forcing just continues
to be the question. Sunday will be the day with the best chances
for rain/storms on this holiday weekend. The front will continue
its slow slide southward on Monday and will stall along the Gulf
Coast for much of next week. /10/
&&
.AVIATION...
00Z TAF discussion:
VFR conditions will prevail tonight through Thursday. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
Jackson 51 80 62 90 / 3 0 0 2
Meridian 50 80 60 89 / 57 0 0 1
Vicksburg 51 81 64 90 / 2 0 0 2
Hattiesburg 50 82 61 89 / 2 0 0 1
Natchez 50 82 64 89 / 1 0 0 1
Greenville 52 80 65 89 / 32 0 0 4
Greenwood 51 79 64 89 / 72 0 0 3
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...None.
LA...None.
AR...None.
&&
$$
12
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
1036 PM EDT Wed May 24 2017
.UPDATE...
Issued at 1036 PM EDT WED MAY 24 2017
Based on the latest radar trends and lack of instability, decided
to remove thunder from the forecast for the remainder of the
night. Also decreased precipitation probabilities across the area
for the rest of tonight per radar trends and the latest model
data, especially the HRRR model, which is more in line with what
is actually occurring. The GFS seemed to wet for the rest of the
night, while the NAM12 was a bit more reasonable as its solution
was fairly similar to that offered by the latest HRRR. The
hazardous weather outlook was also updated to remove mention of
thunder for tonight.
UPDATE Issued at 805 PM EDT WED MAY 24 2017
Went ahead and nixed Tornado Watch 264 early since any remaining
strong storms have moved out of the forecast area. The forecast
grids, zone forecast text product, and the hazardous weather
outlook were also updated based on the watch cancellation.
UPDATE Issued at 608 PM EDT WED MAY 24 2017
Went ahead and shaved 8 of our southwestern and southern counties
off of the current tornado watch. The forecast grids, the zone
forecast text product, and hazardous weather outlook were all
updated accordingly.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 505 PM EDT WED MAY 24 2017
20z sfc analysis shows a stacked low moving through eastern
Kentucky and this is responsible for two separate areas of
thunderstorms this afternoon. The first started out as a large
area of showers over our eastern counties that grew to have
several embedded thunderstorms - all rotating and rather
organized. Concern was greater for the western area of storms
associated with the system`s cold front due to a clear patch in
the clouds allowing for rapid destabilization through the
Cumberland Valley and across much of the JKL CWA in the wake of
the first batch of showers - justifying the watch issuance.
However, just as the watch was going out for those western storms,
the ones in the east strengthened to the point of needing severe
warnings while also training brief, but very heavy, rains through
parts of Floyd and Pike county leading to localized flash
flooding. Now those eastern storms have cleared off and the
western ones are working into eastern Kentucky. We will see how
long they can be sustained and whether there was enough sunshine
ahead of them to make for a favorable environment for further
development and support for the storms. There is a potential for
the watch to be cancelled early depending on these trends.
Readings did make it too the lower 70s ahead of these next storms,
but were in the 60s elsewhere, while dewpoints held in the upper
50s to lower 60s and winds remained rather light beneath the sfc
low and away from any storms.
The models are in good agreement aloft swinging the closed low
through the Ohio Valley with the best energy focused well to the
south of the state tonight though some weaker amounts will swing
through the east this evening and overnight wrapping around to the
north through dawn Thursday. This low then flattens out and works
east of the Ohio Valley by Friday morning with heights rebounding
locally in its wake. Given the model agreement have favored a
blended solution with a strong lean toward the HRRR and other CAMS
in the near term.
Sensible weather will feature the storms settling down by dusk
with showers remaining, mainly to the west and north of the CWA
initially before shifting southeast into the area later tonight.
Lighter rains will then set up over the area into Thursday morning
with some training possible and the need to watch for localized
flooding. The showers will gradually shift northeast and fade out
later Thursday as dry weather returns from southwest to northeast
and eventually clearing later that night. Patchy fog will be
possible in the east this evening and early overnight where the
clouds will be thinnest for a time while patchy - more valley
concentrated - fog will be possible Thursday night.
Again the CONSShort and ShortBlend were used as a starting point
for the grids with only minor adjustments made to temps and
dewpoints through the period. As for PoPs, made some significant
adjustments to them to better represent the spatial and timing
aspects of the shower clusters through Thursday.
.LONG TERM...(Friday through Wednesday)
Issued at 346 PM EDT WED MAY 24 2017
The blended model data was suggesting that after a dry day on
Friday, eastern Kentucky will be in for a period of wet weather
from Friday night through Monday, with another period of rain
possible on Tuesday and Tuesday night. The wettest period looks to
be from Saturday afternoon through Sunday evening, when it appears
that a frontal boundary will stall across the area. Scattered to
numerous showers and storms will possible during this time.
Temperatures during the extended should be running at or slightly
above normal, with daily highs ranging from the upper 70s to lower
80s, and nightly lows in the mid to upper 50s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
ISSUED AT 805 PM EDT WED MAY 24 2017
Scattered showers and a few thunderstorms will be possible across
eastern Kentucky tonight. Conditions at the TAF sites will vary
from VFR to MVFR overnight for the most part. There could be
periods of IFR CIGs from 6Z onward at SYM, 10Z onward at SJS, 11
to 12Z onward at LOZ and SME, and 14Z onward at JKL. These lower
CIGs would be in response to the onset of increased shower and
storm activity across the area, as a large area of low pressure
aloft spins its way across the Great Lakes and Ohio Valley regions
Thursday and Thursday night. Winds should be out of the southwest
at 5 to 10 mph tonight. The winds are expected to shift from the
southwest to west, and increase to 10 to 15 mph across the area on
Thursday, as an area of low pressure moves across the region. The
winds could gust to around 20KTs at LOZ and SME on Thursday,
especially during the afternoon hours.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AR
SHORT TERM...GREIF
LONG TERM...AR
AVIATION...AR
Area Forecast Discussion
National Weather Service Elko NV
415 PM PDT Wed May 24 2017
.SYNOPSIS...Dry weather comes to an end as a series of weak fronts
moves through the area through Today with scattered showers and
isolated thunderstorms. The main storm system will finally exit
the area late Friday with dry and warmer weather returning for the
weekend.
&&
.SHORT TERM...Today through Friday. Isolated to scattered showers
and thunderstorms will cont through the aftn across northern NV N
of I80 and northern/White Pine Counties. Currently the strongest
storms are in central Nye and northern Elko Counties. The best
shear is to the north where a few cells could sustain longer.
Very weak shear is creating an environment more favorable for
pulse type storms in central NV. Nevertheless, strong inverted V
soundings could support wind gusts to near 58 mph. There was
already one gust to 52 MPH in the Owyhee Desert. Storms should
weaken after sunset and the HRRR supports this scenario. However
there could be a couple showers along the I80 corridor overnight.
Another minor concern is the cont wind gusts. A few locations have
been gusting to wind adv criteria, but coverage does not justify
a headline. Regardless, motorists should watch for sudden gusts of
wind while driving this aftn/eve.
Thursday - With the passing frontal system, temps will fall around
10 degrees across NE NV. A few isolated showers could hug the
eastern NV border, but coverage will be sparse.
Friday - The trof axis will clip NE NV and bring enough
moisture/instability for more showers and thunderstorms. Coverage
will be more than Thursday and any one storm should produce
around/less than a tenth of an inch of precip. A couple strong
storms could be possible with small hail and gusty winds,
especially for NE Elko County. Elsewhere, generally cooler
conditions and a pleasant day.
.LONG TERM...Friday night through next Wednesday. Model agreement
is pretty good. There is potentially a lengthy dry period ahead.
Friday night. There could be a few lingering showers across
eastern Nevada in the evening as a positive-tilt trough exits the
region to the east. Low temperatures will be in the 40s.
Saturday through Wednesday. High pressure will expand dramatically
over the Great Basin. Model QPF is showing up as minimal to
nonexistent at least through Tuesday before the ridge potentially
begins to break down. Will keep the forecast dry through Wednesday
with some cumulus buildups possible under the massive ridge
pattern. There could be a thunderstorm or two pop up on any given
afternoon however the tendency would by toward the dry variety
with PWs generally in the low to mid 30s. High temperatures will
rise through the 70s this weekend and into the 80 next week. Low
temperatures will range from the mid 40s to the mid 50s.
&&
.AVIATION...KEKO KELY and KTPH: Periods of showers with a few thunderstorms
may bring MVFR conditions at times this afternoon. West winds will
gust to around 30 kts through this evening. Thunderstorms may
affect KELY again Thursday afternoon.
KWMC: A few showers will pop up near the airport this afternoon
but VFR conditions should hold.ers are expected through Wednesday
with VFR conditions. West winds will be gusty through early this
evening.
&&
.HYDROLOGY...The stretch of the lower Humboldt River from Comus downstream
through Winnemucca to the Humboldt/Pershing County border will
experience minor to moderate flooding through the weekend. A Flood
Warning is in effect.
The Humboldt River at Battle Mountain may drop below flood stage
as early as Thursday. A Flood Warning is in effect.
The Jarbidge River is expected to experience some minor flooding
issues over the next several days. Temperatures will be about 10
degrees cooler for Thursday and Friday which will help to
temporarily slow snowmelt, however high temperatures will warm
back up this weekend and early next week.
Wildhorse Reservoir is still above the spillway. There is no
threat for flooding at this time downstream along the Owyhee
River.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
94/92/92
Area Forecast Discussion
National Weather Service Louisville KY
658 PM EDT Wed May 24 2017
...Updated Forecast and Aviation Discussions...
.Forecast Update...
Issued at 540 PM EDT Wed May 24 2017
Surface low now centered over central Kentucky with warm front
boundary draped across the Bluegrass region. Main concern has been
tornado threat as cluster of storms originating out of middle TN
have lifted northeast through south-central Kentucky into portions
of the Bluegrass and eastern Kentucky. A stripe of better
instability thanks to earlier breaks in the clouds and enhanced
effective shear led to a few rotating storms which did produce some
large hail and damaging winds.
Believe the tornado threat is on the downward trend as we lose the
remaining instability this evening. However, the severe threat will
transition to a flash flooding as training convection slowly pivots
around the low pressure system over central Kentucky. Earlier storms
across Hart and Larue counties produced 2-2.5" of rain in a short
period. The thunderstorms are efficient rain producers with PWATs
running at 1.25".
Latest model guidance shows highest QPF axis through tomorrow
morning likely to setup across portions of southern Indiana and
north central Kentucky. HRRR and WRF ARW show convection pivoting
slowly across the area this evening and tonight. Additional amounts
of 1 to 2 inches not out of the question. Locally higher amounts
possible as well.
As a result, in coordination with ILN and IND, will issue a Flash
Flood Watch in effect now through mid morning Thursday for areas
mainly east/northeast of Louisville metro. Some of these areas
picked up quite a bit of rain last weekend and overall, Flash Flood
guidance values are low in these counties.
Updated products and graphics will out shortly.
&&
.Short Term (Now through Thursday Night)...
Issued at 315 PM EDT Wed May 24 2017
...Severe Storms Possible Until Early Evening East of I-65...
Closed upper low over the mid-Mississippi Valley is starting to fill
in, but a vort lobe lifting through the Tennessee Valley ahead of it
has really sharpened and may be taking over as the main player in
our weather. Surface reflection is a deepening 995mb low now lifting
through south-central Kentucky. Axis of marginal instability running
just west of the I-75 corridor, with backed low-level winds,
continues to support a severe threat that includes the potential for
brief tornadoes. Thus we remain under a Tornado Watch roughly east
of a line from Frankfort to Greensburg to Tompkinsville, though we
will spend the late afternoon hours trimming counties from the south
end of the watch as surface winds shift to NW.
Precip shield associated with the upper system will take a bit
longer to exit, with additional rainfall approaching an inch along
the I-65 corridor, though locally higher totals are quite likely in
the more convective activity to the east. Expect the pattern to slow
down due to some Fujiwhara effect between the two upper lows, and we
will end up with a stacked system somewhere near Cincinnati by
daybreak on Thursday. POPs tonight will taper from likely
along/north of I-64 to a low chance across south-central Kentucky.
Elongated north-south trofiness early on Thursday will support
scattered to numerous showers with the highest POPs across the
Bluegrass region, closer to the low pressure center. Precip chances
will taper down fairly sharply in the afternoon, and no mention of
thunder given a lack of instability. Clouds and precip will hold
temps in check, especially in the Bluegrass where we may not get out
of the 60s. Expect dry conditions, gradual clearing, and seasonable
temps Thursday night as shortwave upper ridging takes over.
.Long Term (Friday through Wednesday)...
Issued at 305 PM EDT Wed May 24 2017
Expect unsettled weather for much of the holiday weekend, bookended
by dry and pleasant days on Friday and Monday. Shortwave ridging on
Friday will keep us dry for most of the day, but a weak disturbance
passing just to our north will warrant a slight chance POP for
southern Indiana late in the day. A weak front will drop into the
Ohio Valley Friday night and hang up parallel to the flow aloft.
For most of Memorial Day weekend, the front will remain nearly
stationary over the Ohio Valley, and a series of disturbances will
interact with this front to spawn multiple rounds of showers and
storms. Best chances will be Sat night into Sun as an upper trof
digs into the Plains, and the better dynamics aloft could allow for
a few stronger storms as well. Cold front looks to pass through
Sunday night, with a mid level dry slot bringing drier conditions
into Memorial Day.
Another chance for showers arrives Tuesday, with a few afternoon
thunderstorms possible as a shortwave embedded in the parent trough
rotates through our region.
&&
.Aviation...()
Issued at 657 PM EDT Wed May 24 2017
Low pressure over north central Kentucky will move into southwest
Ohio overnight. Waves of showers and some thunderstorms will pivot
around this low, mainly impacting SDF and LEX through this TAF
period. Expect the steadiest rain at SDF and LEX through late this
evening, then a lull, before rain bands pivot back over the area for
Thursday morning.
Ceilings overall will begin to lower as saturation and cooling take
effect. Good consensus in the model forecasts that IFR ceilings will
encompass much of central Kentucky after midnight then linger
through Thursday morning. Improvement to MVFR then VFR expected late
in the period Thursday afternoon.
Winds will become westerly and generally stay in that direction
through the period. As the pressure gradient tightens Thursday late
morning and afternoon, wind gusts 20 to 25 kts are likely.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...Flash Flood Watch through Thursday morning for INZ077>079-092.
KY...Flash Flood Watch through Thursday morning for KYZ031>037-
039>043-048-049.
&&
$$
Update...ZT
Short Term........RAS
Long Term.........RAS
Aviation...ZT
Area Forecast Discussion...UPDATED
National Weather Service Chicago/Romeoville, IL
836 PM CDT Wed May 24 2017
.UPDATE...
836 PM CDT
Rain showers are still retrograding westward across the eastern
and central forecast area early this evening, but are beginning
to show a coverage fade. These showers are associated with the
mid-level circulation across eastern Indiana/western Ohio. This
wave will move slowly north-northeast overnight with wraparound
700-925mb moisture over the area gradually easing. Showers should
have an associated slow dissipation through tonight.
With the surface reflection deepening to around 992 mb by daybreak
near Cincinnati, the pressure gradient will actually tighten
overnight over the area. The northerly wind component should
preclude much for fog across most of the area, with RAP
hydrolapses also favoring stratus more than fog. Confidence in
clearing during the day Thursday remains low, though building
heights across north central Illinois should at least allow for
some holes to develop there, similar to seen in eastern Iowa this
afternoon.
MTF
&&
.SHORT TERM...
215 PM CDT
Through Thursday...
Sharp upper level trough with pinwheeling lows will continue to
impact the region in the near term bringing overcast skies
areawide and scattered showers. Water vapor imagery this
afternoon reveals two upper lows embedded within a broader
longwave trough centered over the Mississippi Valley. A western
low is digging south across Missouri into Arkansas while another
low is lifting north across the Ohio Valley. The western low
resulted in some scattered showers over the western CWA earlier
today but is otherwise exiting the area with mid level height
rises building across the mid and upper Mississippi Valley. More
widespread precipitation is in place with the eastern low and some
of the showery activity with this low will impact areas mainly
east of the I-55 corridor through the remainder of the afternoon
and evening. There is some very modest instability over
northwestern Indiana, 100-200 J/kg MLCAPE which may result in an
isolated embedded thunderstorm or two, but overall lightning
potential is low for the CWA.
The western upper low is progged to dig into the deep south late
this evening and overnight which will help kick the eastern low
farther east out of the CWA. This will result in diminishing
precip chances through the late evening and overnight hours.
Lingering low level cyclonic flow through mid afternoon Thursday
will likely keep much of the CWA locked under cloud cover, but
ridging building into our west mid to late in the afternoon should
result in some clearing west and perhaps a few peeks of sunshine
east. Temperatures are expected to be several degrees warmer
tomorrow, with highs in the upper 60s to around 70 inland, but
only in the 50s and low 60s along the lake front.
Deubelbeiss
&&
.LONG TERM...
318 PM CDT
Thursday night through Wednesday...
There are not many periods without a mention of rain from late in
the week through next Wednesday, but the window from late Thursday
into early Friday appears to be one exception. Other breaks appear
likely early Saturday and again Sunday night. This is not to say
the other periods are likely to see widespread rainfall, but chances
increase for most afternoons in response to diurnal heating, the
ongoing presence of longwave cyclonic energy aloft, and the timing
of shortwaves moving across the area.
The axis of a surface and upper level ridge positioned over the
Plains this afternoon will push into the western Lakes by early
Friday but by midday Friday already appears to be east of the area.
Deterministic guidance from the ECMWF/GEM/GFS solutions all show an
embedded shortwave over the area by this time in the more zonal flow
upstream from the departing ridge. The surface reflection of this
upper shortwave is handled quite differently by the different
models, but all suggest a wave will develop along a baroclinic zone
running south of the area. Given model differences it is difficult
to pin down specifics, but generally the better chances of showers
and thunderstorms would be focused across the southern half of the
forecast area Friday afternoon and evening.
This baroclinic zone drops south and allows a weak ridge to move
into the area early Saturday, but then the next surface wave
develops upstream and lifts toward the area late Saturday along with
the next upper shortwave. Models again show poor agreement with the
handling of these features, so we have not included more than chance
POPs for Saturday afternoon and evening.
By late in the weekend the next upper low drops from central Canada
into the Great Lakes and remains overhead through late Tuesday.
Chance POPs persist each day in this period, especially in the
afternoons and evenings, and then drop to slight chances by
Wednesday as the upper low begins to lift off to the east.
Lenning
&&
.AVIATION...
For the 00Z TAFs...
641 pm...Main forecast concern is cigs through Thursday morning
as well as the chance of fog overnight and showers this evening.
Ifr/lifr cigs across the far southwest part of Lake Michigan into
gyy have not moved west toward ord/mdw thus far...but confidence
on what these low cigs will do after sunset is low. Maintained sct
mention at ord/mdw but trends will need to be monitored this
evening. Guidance varies on cigs overnight...between ifr and mvfr.
Previous forecast of low mvfr cigs seems most likely and will
again need to monitor trends. Cigs will gradually lift Thursday
morning becoming vfr Thursday afternoon and likely scattering out.
Fog is possible overnight into Thursday morning...and will likely
be dependent on how much...if any...lower cigs scatter out. This
seems possible across northwest IL and at rfd but further east...
confidence too low to include any mention of fog.
Scattered showers have spread west into eastern IL late this
afternoon and appears the western edge will likely remain along a
pnt/c09/mdw line. Close enough to continue vicinity mention at ord
but areas west of this line likely to remain dry. These showers
will slowly end mid/late this evening as they pull back to the
east.
North/northeast winds will turn more to the north/northwest later
this evening and are expected to remain north/northwest or
northerly through Thursday afternoon with speeds 10-15kts. A lake
breeze is possible Thursday afternoon...shifting winds back to the
north/northeast but only medium confidence. cms
&&
.MARINE...
318 PM CDT
Low pressure over Kentucky today will move into Ohio by Thursday
and then quickly off the New England coast by Friday. This low
will support northerly flow across the lake through late
Thursday. Winds will be lighter and more variable Friday and
Saturday as a weak ridge builds over the lake. Winds eventually
increase from the southwest later in the weekend as the next low
pressure system moves slowly across Ontario Saturday and toward
James Bay by Monday afternoon.
Lenning
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...Beach Hazards Statement...ILZ006-ILZ014 until 7 PM Thursday.
IN...Beach Hazards Statement...INZ001-INZ002 until 7 PM Thursday.
LM...Small Craft Advisory...IL nearshore waters until 10 AM Thursday.
Small Craft Advisory...IN nearshore waters until 4 PM Thursday.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion...UPDATED
National Weather Service Mobile AL
658 PM CDT Wed May 24 2017
.DISCUSSION...Updated for latest marine discussion below.
&&
.MARINE...Latest surface data collection platforms over the marine
area indicate that wind speed has lowered to below small craft
advisory criteria for portions of area bays and sounds from
Perdido Bay eastward. Will replace with small exercise caution
headlines. For southern Mobile Bay and the adjacent MS Sound,
west northwest winds remain in advisory criteria. The latest high
resolution HRRR guidance suggests that wind speeds will remain so,
there, over the next few hours and have thus extended the
advisory for these areas thru 10 PM. For the open Gulf waters,
advisory remains unchanged. /10
&&
.PREV DISCUSSION... /issued 635 PM CDT Wed May 24 2017/
DISCUSSION...Updated for latest aviation discussion below.
AVIATION...
00Z issuance...VFR conditions forecast at the terminals with passing
cu this evening having bases above 6 kft. Scattered shra possible
over the interior with departures heading northbound. Vsby ok.
Westerly winds 5 to 10 knots. /10
PREV DISCUSSION... /issued 355 PM CDT Wed May 24 2017/
NEAR TERM /Now Through Thursday/...An upper level low pressure
system continues to propagate southward across southern MO toward
northern AR this afternoon, while a broader scale upper level trough
extends across the Mississippi/Tennessee Valleys and Central Gulf
Coast region. A surface cold front has pushed to the east of our
forecast area this afternoon, with gusty westerly winds and lower
dewpoints in the 50s spreading across our region. While earlier
convection has moved to the east of the forecast area along and
ahead of the front, visible satellite imagery shows an agitated
cumulus field spreading into interior southeast MS and southwest AL
along the trough axis, and there will still be opportunity for a few
isolated light rain showers to develop over the interior through
this evening as the trough axis moves across the region. We will
keep a 20% POP in the forecast this evening mainly north of Hwy 84.
We otherwise expect clearing skies late tonight into Thursday as a
drier northwest flow aloft spreads into our region in the wake of
the departing trough axis. A building surface ridge, clearing skies
and a drier airmass will support cooler low temperatures tonight
with readings in the lower to mid 50s over most interior areas, with
upper 50s to mid 60s expected near the immediate coast and beaches.
Highs Thursday are forecast to range from around 80 to the lower 80s
across most locations. /21
SHORT TERM /Thursday night Through Saturday night/...The pleasant
break from humidity quickly vanishes heading into the short term
period. Surface high pressure builds into the western Atlantic and
onshore flow is reestablished across the central Gulf coast by
Friday. Despite increasing low level moisture and cloudiness,
however, the short term remains rain free thanks in large part to
mid-level subsidence beneath an upper high parked over the
central and northern Gulf. High temperatures will reach the upper
80`s to low 90`s inland and the mid 80`s along the beaches both
Friday and Saturday afternoons. Overnight lows gradually warm
into the weekend as moisture returns to the area, with temps in
the low to mid 60`s Thursday night becoming low to mid 70`s by
Saturday night.
/49
LONG TERM /Sunday Through Wednesday/...Unsettled weather returns
for much (if not all) of the long term period. A large and deep
upper-level low pressure system over eastern Canada pushes the
high pressure in the central Gulf farther south and east. This
shift places a more organized zonal upper-level flow over the
central Gulf coast along the southern periphery of the
aforementioned Canadian low. Beneath this setup, a weak frontal
boundary sags into the local area before stalling and, save for
some minor shifting due to mesoscale forcing mechanisms (e.g.,
sea/land breezes), remains stationary into next week. A combination
of the stationary boundary, onshore surface flow, and a series of
impulses embedded within the upper-level flow will support daily
shower and thunderstorm activity beginning as early as Sunday
afternoon/evening and lasting into the middle part of next week.
In terms of temperature, Sunday likely remains hot (upper 80`s to
low 90`s inland, mid 80`s along the beach) before the front
enters the area. Monday through the middle of next week, however,
will see highs only reaching the mid 80`s as cloud cover and
thunderstorms help to mitigate daytime heating. Low temps will
depend on the location of the stationary front each night. Sunday
night, most locations will continue to see lows in the low to mid
70`s before the boundary stalls across the area. Heading into the
rest of the long term (Monday and Tuesday nights), temps north of
the stalled front will dip as low as the mid 60`s. Temps south of
the front and along area beaches will continue to stay in the low
to mid 70`s.
/49
MARINE...A moderate to strong west to northwest flow will prevail
over the marine area tonight as high pressure builds into the
western and central Gulf behind the frontal passage. A Small Craft
Advisory will continue until 7 PM for area bays and sounds where
winds around 20 knots are expected before gradually diminishing this
evening. A stronger west to northwest flow and elevated seas up to 6-
9 feet will support keeping a Small Craft Advisory over the coastal
waters through late tonight. Surface high pressure will build from
the central Gulf of Mexico Thursday to the eastern Gulf and FL
Peninsula Friday through early next week. Moderate westerly flow
Thursday should gradually become southerly to southwesterly Friday
through Monday. Seas also gradually subside late this week into the
weekend. /21
&&
.MOB WATCHES/WARNINGS/ADVISORIES...
AL...High Rip Current Risk until 7 PM CDT this evening for ALZ265-266.
FL...High Rip Current Risk until 7 PM CDT this evening for FLZ202-204-
206.
MS...None.
GM...Small Craft Advisory until 4 AM CDT Thursday for GMZ650-655-670-
675.
Small Craft Advisory until 10 PM CDT this evening for GMZ631-632.
&&
$$
This product is also available on the web at:
http://weather.gov/mob
by that time. See the previous forecast discussion below. Huston
Strong winds in the Snake Plain will diminish this evening between 8
and 9 pm MDT with setting sun and decreasing surface pressure
gradient. Cold air and moisture moving south from British Columbia
will drop into Idaho tonight and Thursday to lower afternoon
temperatures about 7 to 10 degrees and bring some scattered showers
over the Central Mountains and Upper Snake Highlands. Snow levels
only dip to around 7800 feet elevation. This trough remains over
Southeastern Idaho on Friday before finally moving off to the east
Saturday. RS
.LONG TERM...Saturday night through Wednesday. GFS and ECMWF
ensembles give high confidence in established upper ridge in the
long-term period. The ridge axis should stay over WA/OR, leaving
Idaho in a broad northwesterly wind aloft. Dynamics for large-scale
ascent is lacking, but deterministic models persist in generating
showers and thunderstorms owing to diurnal heating and orographic
lift. Temperatures will edge upward through the period with highs
starting in the mid 70s across the Snake Plain on Sunday, to the mid
80s by Wednesday. Hinsberger
&&
.AVIATION...Dry cold front moving through the area will keep wind
gusts around 35 to 45 kts across the Snake Plain this afternoon and
early evening. Given the dry nature of the front and the time of
year, areas of blowing dust may bring lowered visibility to KIDA and
KPIH. We have high confidence in the strong winds today, lower
confidence in the areal extent, intensity, and duration of the
blowing dust. Opted to put the MVFR visibilities in a TEMPO group
for this afternoon rather than predominant. Hinsberger
&&
.HYDROLOGY...Temperatures will play a roll in snow melt and
runoff the next week or or more. Cooler temperatures Thursday and
Friday will help slow the melting, but by Saturday temperatures
begin a warming trend. A high pressure ridge expected to move
inland early next week will bring additional warming. Rain showers
over the mountains the next two days will add some new snow to
the upper peaks and rain on mid and lower slopes. RS
&&
.PIH WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
827 PM EDT Wed May 24 2017
.UPDATE...
Regional radar composite is showing a broken band of
thunderstorms just north of the forecast area, which is
forecast to push south through the area overnight ahead of
the cold front. The HRRR is forecasting that this line will
intensify somewhat after midnight as it moves into the
Tampa Bay area, although a much more compact line of storms
is forecast than what was seen earlier.
Apart from the next round of thunderstorms, the biggest
area of concern remains the wind, although winds are
gradually subsiding. The Lake Wind Advisory is still up
through 10 PM, and coastal flood statements and rip current
advisories are still in effect until Thursday morning.
Some additional tweaks were made to the rain chances and
weather grids from what was updated earlier this evening. No
other changes are planned for the evening update.
&&
.AVIATION...
Most of the storm activity has moved away from the TAF
sites, but another band of showers or storms is forecast to
pass north to south through the overnight hours with the
front, with brief IFR conditions possible. Widespread MVFR
ceilings will continue to impact the area TAF sites through
the overnight hours, although occasional VFR periods will
be possible. Otherwise, winds will turn to more westerly by
Thursday morning.
&&
.MARINE...
Winds will start to subside through the next few hours, but
seas are expected to remain at or above advisory levels
through the overnight hours as the cold front passes through
the area. West to northwest winds of 15-20 knots are still
expected Thursday morning, so cautionary headlines will
still be needed after the advisory is dropped, with
conditions continuing to improve through the rest of the
day.
&&
.Preliminary Point Temps/PoPs...
TPA 74 82 68 86 / 40 20 0 0
FMY 76 83 69 90 / 70 50 0 0
GIF 71 83 65 89 / 50 20 0 0
SRQ 76 82 68 84 / 60 20 0 0
BKV 70 80 59 86 / 40 20 0 0
SPG 75 81 71 85 / 50 20 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through Thursday morning for Coastal
Charlotte-Coastal Hillsborough-Coastal Lee-Coastal
Manatee-Coastal Sarasota-Pinellas.
Lake Wind Advisory until 10 PM EDT this evening for
Coastal Charlotte-Coastal Citrus-Coastal Hernando-
Coastal Hillsborough-Coastal Lee-Coastal Levy-Coastal
Manatee-Coastal Pasco-Coastal Sarasota-DeSoto-Hardee-
Highlands-Inland Charlotte-Inland Citrus-Inland
Hernando-Inland Hillsborough-Inland Lee-Inland Levy-
Inland Manatee-Inland Pasco-Inland Sarasota-Pinellas-
Polk-Sumter.
Gulf waters...Small Craft Advisory until 8 AM EDT Thursday for Charlotte
Harbor and Pine Island Sound-Coastal waters from
Bonita Beach to Englewood FL out 20 NM-Coastal waters
from Englewood to Tarpon Springs FL out 20 NM-Coastal
waters from Tarpon Springs to Suwannee River FL out
20 NM-Tampa Bay waters-Waters from Bonita Beach to
Englewood FL out 20 to 60 NM-Waters from Englewood to
Tarpon Springs FL out 20 to 60 NM-Waters from Tarpon
Springs to Suwannee River FL out 20 to 60 NM.
&&
$$
UPDATE/AVIATION/MARINE...18/Fleming
UPPER AIR...27/Shiveley
DECISION SUPPORT...25/Davis