Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/15/19
Area Forecast Discussion
National Weather Service Quad Cities IA IL
523 PM CDT Mon Oct 14 2019
...00z AVIATION UPDATE...
.SYNOPSIS...
Issued at 226 PM CDT Mon Oct 14 2019
After a cold start with frost, sunny skies prevailed across the
area. Below normal temperatures were seen, as weak ridging aloft
moved east over the upper Great Plains and surface high pressure
drifted east over the Ohio river valley.
At 2 pm, temperatures were in the 50s, with dewpints in the 30s.
Strong shortwave to impact the area overnight tonight, was seen
on WV imagery moving over Montana.
&&
.SHORT TERM...(This Evening through Tuesday)
ISSUED AT 226 PM CDT Mon Oct 14 2019
Main forecast concern is on precipitation chances after midnight
tonight and frontal passage Tuesday, along with cloud trends
impacting temperatures.
Tonight...Other than some mid and high level clouds streaming
over northern Iowa, much of the area will see mostly clear skies
this evening. An area of low pressure will track east over South
Dakota and into Minnesota, with an associated warm front lifting
northeast over Iowa. Strong WAA on the nose of the low level jet
will allow increasing clouds and precipitation to develop after
midnight. Some isolated thunderstorms will be possible as well as
18z RAP 700-500 mb theta-e lapse rates go negative overnight.
Latest HREF members and HRRR suggest precipitation will not start
until after 07z this evening, due to dry mid level air and I am
not expecting much in the way of QPF tonight, with rain amounts
less than a tenth of an inch. Some models even suggest some of our
area may be completely dry, with just our far north and far south
seeing precipitation. South winds and increasing clouds will keep
temperatures much warmer than previous mornings, with lows only
dropping into the lower 40s north, to lower 50s south.
Tuesday...Cold frontal passage to push through the area late
Tuesday morning, with steady or slowly falling temperatures during
the afternoon. Strong CAA with gusty northwest winds will be seen
behind the front along with clouds. High temperatures may be a
challenge due to cloud cover. I am currently going with upper 50s
for highs northwest of a Iowa City to Freeport line to the lower
60s south, but if clouds remain overhead for a longer period of
time or go further south, these readings may be too high.
.LONG TERM...(Tuesday Night through Monday)
ISSUED AT 226 PM CDT Mon Oct 14 2019
Quiet and dry conditions will start the extended forecast with
rising temperatures. Increasing rain chances will be seen late
Friday and into early next week.
Dry northwest flow and high pressure is expected Tuesday night
through much of Friday, with temperatures going above normal by
the end of the work week. Wednesday will be a rather brisk and
cold day, as high pressure builds into the region and 850 temps
remain below 0C across the entire CWA. Clouds and CAA will once
again keep highs from rising much and will only reach the upper
40s and lower 50s.
Friday night-Monday...the weather becomes more active with a
southwest flow pattern setting up. Several waves will move
through the flow, with the strongest expected to impact the area
late Sunday and into Monday. Deep moisture will return with an
open Gulf and there will be the possibility of significant
rainfall as we head into next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
ISSUED AT 510 PM CDT Mon Oct 14 2019
A fast moving cold front will bring a chance of showers and lower
ceilings to mainly the river sites late tonight until mid morning
Tuesday. This will be followed by brisk W/NW winds, and some
lower ceilings evolving during the afternoon continuing beyond the
end of the TAF cycle as area becomes entrenched in cold, cyclonic
flow.
Precipitation...
Chance of showers roughly in the 08z-14z timeframe. Have handled
with PROB30 mention. Isolated storm is possible, but probability
appears too low at this time for any mention.
Visibility...
Predominantly VFR, with a low probability of very brief MVFR/IFR
in the strongest showers or isolated storms.
Ceilings...
Unlimited for most of tonight. Late tonight through Tuesday AM,
expecting VFR with a period of MVFR at the river sites.
Tuesday PM developing widespread MVFR at the northern sites (DBQ,
CID) evolving further south at MLI and BRL late in the period and
just beyond.
Winds...
Tonight, easterly turning southerly and increasing above 10 kts.
Strengthening low level jet will foster LLWS after 06z until 12z
with winds increasing to around 35-40 kts from S/SW at 2kft agl.
Cold front passes by mid to late AM with winds shifting from the
west/northwest becoming gusty 20-30+ kts during the PM.
&&
.HYDROLOGY...
Issued at 1007 AM CDT Mon Oct 14 2019
No significant changes were made to river forecasts this morning.
River levels on tributaries that are above flood stage continue to
fall. Along the Mississippi, a crest currently in Dubuque will
continue working downstream, and will reach the Quad Cities by late
Tuesday. This will continue working downstream, but is expected not
to produce significant rises in levels.
Looking ahead, there is a chance of rain showers across the entire
hydrologic service area tonight. However, forecast QPF amounts
below 0.10" will have no impact on current river levels.
Active weather may return to the region this weekend and early next
week as the upper level flow becomes more active and moisture is
brought back north from the Gulf of Mexico. The Climate Prediction
Center is forecasting a high probability (60-70%) of above normal
precipitation for the entire mid-Mississippi River Valley from Oct
19-23. While it is too early to pinpoint exact rainfall amounts for
this period, the potential does exist for renewed rises or prolonged
falls along area rivers by mid to late next week. Please stay tuned
to the latest forecasts and information.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...Gross
SHORT TERM...Gross
LONG TERM...Gross
AVIATION...McClure
HYDROLOGY...Speck
Area Forecast Discussion
National Weather Service Green Bay WI
947 PM CDT Mon Oct 14 2019
Updated aviation portion for 06Z TAF issuance
.SHORT TERM...Tonight and Tuesday
Issued at 258 PM CDT Mon Oct 14 2019
Mostly sunny skies prevailed across the region this afternoon.
Temperatures were mainly in the middle 40s to around 50 degrees.
For tonight, skies will start out mostly clear then clouds will
be on the increase as the next system approaches from the west.
The chance of showers will increase towards 12z. The main question
is how far east the precipitation will make it into the forecast
area. The latest HRRR model create much uncertainty as this model
focus the precipitation across north- central Wisconsin and the
remainder of the region is dry as of 12z. The other models have
chances of rain spreading all the way east into northeast
Wisconsin. Will have the highest chances of rain across north-
central Wisconsin, then taper precipitation chances to the east.
Low temperatures tonight will likely occur this evening or
shortly after midnight, then slowly rise towards sunrise on
Tuesday.
For Tuesday, low pressure and the associated cold front will
move across the region. Models indicated 850mb LI`s down to
near zero and steep mid level lapse rates to support the mention
of an isolated thunderstorms. The track of the low will allow
for the warm sector to make it into our southern counties where
highs in the lower to middle 50s are expected. Highs across the
north will only be in the lower to middle 40s.
.LONG TERM...Tuesday Night Through Monday
Issued at 258 PM CDT Mon Oct 14 2019
Low pressure will be situated over far northeast WI/south central
Upper Peninsula on Tuesday evening, as a powerful upper level low
moves through northern WI. Likely/Categorical pops are warranted
across northern WI during the evening, with chance pops farther
south. Dynamic cooling may cause the rain to mix with snow across
far north central WI, but any accumulations should remain under an
inch. Favorable over-water fetch (NNW) and instability (Lake-H8
delta-t`s of 14-16 C increasing to 16-18 C) will support continued
lake-enhanced shower activity over north central WI and northern
Door county through Wednesday morning, but showers should decrease
elsewhere. A few snow showers may continue to mix in across
northern WI. Strong north-northwest winds will develop late
Tuesday night and continue into Wednesday, with possible gales on
Lake Michigan.
A surface ridge will bring dry conditions Wednesday night through
Friday. As the ridge shifts east on Friday, much milder air will
arrive, with highs rising into the upper 50s and lower 60s.
A chance of showers will arrive Friday night into Saturday as a
cold front and short-wave trof arrive. This system should shift
east of the region by Saturday evening, bringing a mainly dry end
to the weekend.
A stronger low pressure is expected to arrive Sunday night into
Monday, along with a threat of widespread rain.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 946 PM CDT Mon Oct 14 2019
VFR conditions expected through much of tonight with a steady
increase in mid to high clouds from the west overnight. Rain
showers will arrive across central and north-central Wisconsin
between 09z and 12z, then into northeast Wisconsin between 12z and
15z. Rain will continue through the morning as an area of low
pressure and associated cold front move across the region.
Ceilings will drop into IFR/MVFR categories very late tonight and
especially during the day Tuesday. These lower ceiling will then
linger into Tuesday night. LLWS still looks like a possibility as
a temperature inversion keeps the stronger winds aloft from
mixing down to the surface. The wind shear will come to an end
Tuesday morning as the system moves across the region and deeper
mixing occurs. Some snow is possible across the far north Tuesday
night as the system departs the area and some lake enhancement
occurs.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....Eckberg
LONG TERM......Kieckbusch
AVIATION.......Cooley
Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
912 PM CDT Mon Oct 14 2019
.UPDATE...
Updated for evening discussion.
&&
.DISCUSSION...
For the evening update, ongoing light precip continues mainly
over the S half with only low end measuring precip. The trend for
the period as we approach midnight and just after is for the light
precip to break up some. As we approach 3-5am, better lift will
be moving east and we will see a better low level response and
moisture transport and convergence will increase between 5-10am.
The result will be a rapid increase in precip coverage along with
rain rates as much higher moisture content air will be used during
the day Tue. The location for this will be along and N of I-20,
but S of Hwy 82. The latest HRRR has the heavier stripe of precip
closer to I- 20 and this has support from the latest 00z NAM. I
would like to see the 00z hi-res suite (HREF) before making any
adjustments, but that will not be out until 1030-1100pm. To get
the messaging out before the news cycle, I`ll make the addition to
the FF watch now. The going graphics and HWO are on track. /CME/
Prior discussion below:
Tonight and Tuesday: Dynamic weather will take shape across the area
during this time frame. Presently, expansive rain shield has
developed from east TX, across central LA and into southern MS north
of the coastal baroclinic zone as low to mid level winds have
backed in response to storm system digging over the Desert
Southwest. As the coastal boundary moves inland and winds
increase, strong isentropic ascent will result in a band of heavy
rain setting up along and north of Interstate 20 and south of Hwy
82 late tonight and into Tuesday. Rainfall may be especially heavy
considering the depth of moisture with PWs at or above 2.25" as
the feed continues from the tropical system near Baja. Model
sooundings are also indicating transient pockets of MAUL moving
through the precipitation axis which will result in periodic
convective bursts of heavier rainfall. Will issue FFA along the
axis of heaviest expected precipitation.
Also of concern by Tuesday afternoon will the severe potential over
the south. The warm sector will surge inland after sunrise with mid
70s dewpoints moving into portions of northeast LA and southern MS
by noon. Breaks in the cloud cover in these area will send
temperatures up to around 80. While lapse rates are not that
impressive, these temp/dewpoint combinations will result in ML CAPEs
around 1500 J/kg. This along with bulk shear values of 20-25 knots
at 0-1km and 40-50 knots at 0-6km may result in a few severe storms,
provided some low level lifting mechanism can be found./GG/
Wednesday through the Weekend: A shower and/or thunderstorm can`t
be ruled out Wednesday early morning in southern parts of the
region as lingering convection from thunderstorms the evening
before clears out. A cold front will be pushing through the region
Wednesday morning and will bring drier weather Wednesday
afternoon through Friday. Along with this cold front, a mid-level
ridge will build in over the western part of the CONUS which will
also help aid in drier weather during this time thanks to
subsident air and building high pressure.
There will be a return of moisture for the weekend as the then old
front lifts north slightly and bring rain chances to the region for
the weekend. A few showers will be possible both Saturday and
Sunday. Highs look to range from the mid 60s in the north to low
70s in the south Wednesday and Thursday. As for lows Thursday-
Friday, values look to range in the mid to upper 40s in the
northern half and near or at 50 degrees in the south. Highs
Friday-Sunday will warm back into the upper 70s to low 80s./JNE/
&&
.AVIATION...
00Z TAF discussion:
Light rain shield over the SW/S areas continues to
slowly expand eastward with time. The leading edge is mainly
sprinkles and not measuring much. Guidance supports this activity
breaking apart this evening before shifting more along the I-20
corridor around and after midnight with the better precip coverage
expanding from that and into the daytime hours Tue. As for flight
restrictions, look for IFR conditions to spread from S to N later,
mainly in the 07-11z time window. However, look for LIFR conditions
to build in much sooner across the far southern sites between 01-
04z. /CME/
&&
.PRELIMINARY POINT TEMPS/POPS...
Jackson 65 77 64 70 / 91 99 70 19
Meridian 64 75 66 72 / 83 100 76 22
Vicksburg 66 78 62 69 / 83 97 70 16
Hattiesburg 66 82 69 76 / 57 78 80 36
Natchez 67 81 65 69 / 49 95 82 30
Greenville 63 73 56 65 / 93 100 48 6
Greenwood 63 72 57 67 / 82 97 50 7
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Flash Flood Watch from 3 AM CDT Tuesday through Tuesday evening
for MSZ034>052.
LA...Flash Flood Watch from 3 AM CDT Tuesday through Tuesday evening
for LAZ007>009-015-016.
AR...Flash Flood Watch from 3 AM CDT Tuesday through Tuesday evening
for ARZ074-075.
&&
$$
CME/GG/JNE/