Winter Storm Watch 3, NWS St. Louis, MO

Adams County, IL, Bond County, IL, Brown County, IL, Calhoun County, IL, Clinton County, IL, Fayette County, IL, Greene County, IL, Jersey County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Montgomery County, IL, Pike County, IL, Randolph County, IL, Saint Clair County, IL, Washington County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Iron County, MO, Jefferson County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Madison County, MO, Marion County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Ralls County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Shelby County, MO, Warren County, MO, Washington County, MO

330 
WWUS43 KLSX 282150
WSWLSX

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE ST LOUIS MO
350 PM CST FRI FEB 28 2014

...MAJOR WINTER STORM TO AFFECT THE REGION SATURDAY NIGHT THROUGH
SUNDAY NIGHT...

ILZ095>097-MOZ018-019-026-027-034-035-011000-
/O.CON.KLSX.WS.A.0003.140302T0000Z-140303T1200Z/
ADAMS IL-BROWN IL-KNOX MO-LEWIS MO-MARION MO-MONROE MO-PIKE IL-
RALLS MO-SHELBY MO-
INCLUDING THE CITIES OF...HANNIBAL...QUINCY
350 PM CST FRI FEB 28 2014

...WINTER STORM WATCH REMAINS IN EFFECT FROM SATURDAY EVENING
THROUGH LATE SUNDAY NIGHT...

* TIMING...SNOW TO MOVE INTO THE AREA SATURDAY NIGHT...CONTINUE
  THROUGHOUT THE DAY ON SUNDAY...AND PERSIST THROUGH SUNDAY
  NIGHT.

* ACCUMULATIONS...SNOW ACCUMULATIONS OF 8 TO 10 INCHES.

* WINDS...NORTH 10 TO 15 MPH WITH GUSTS UP TO 20 MPH.

* IMPACTS...SNOW ACCUMULATION WILL CREATE HAZARDOUS TRAVEL 
  CONDITIONS SATURDAY NIGHT THROUGH SUNDAY NIGHT OVER NORTHEAST 
  MISSOURI AND WEST CENTRAL ILLINOIS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WATCH IS ADVANCED NOTICE THAT SEVERE WINTER
WEATHER IS POSSIBLE IN THE WATCH AREA...IT DOES NOT MEAN IT IS A
CERTAINTY. THOSE IN THE WATCH AREA SHOULD BEGIN PREPARING IN CASE
THE STORM DOES MATERIALIZE. IF YOU HAVE TRAVEL PLANNED...YOU MAY
WANT TO ADJUST YOUR TRAVEL TIME TO AVOID THE STORM. ALSO...YOU
SHOULD USE THIS ADVANCED NOTICE TO MAKE CERTAIN YOUR VEHICLE IS
WINTERIZED. MAKE PREPARATIONS AT HOME BY STOCKING EMERGENCY
SUPPLIES...SUCH AS FOOD...MEDICINE...AND EXTRA HEATING FUEL...
JUST IN CASE THE STORM MAKES TRAVEL IMPOSSIBLE. THIS IS
ESPECIALLY IMPORTANT FOR THOSE LIVING IN RURAL AREAS.

&&

$$

ILZ058>060-064-065-098>100-MOZ036-041-042-047>052-059>064-011000-
/O.CON.KLSX.WS.A.0003.140302T0000Z-140303T1200Z/
AUDRAIN MO-BOND IL-BOONE MO-CALHOUN IL-CALLAWAY MO-COLE MO-
FAYETTE IL-FRANKLIN MO-GASCONADE MO-GREENE IL-JERSEY IL-
LINCOLN MO-MACOUPIN IL-MADISON IL-MONITEAU MO-MONTGOMERY IL-
MONTGOMERY MO-OSAGE MO-PIKE MO-ST. CHARLES MO-ST. LOUIS CITY MO-
ST. LOUIS MO-WARREN MO-
INCLUDING THE CITIES OF...BOWLING GREEN...COLUMBIA...
EDWARDSVILLE...JEFFERSON CITY...LITCHFIELD...MEXICO...
ST CHARLES...ST LOUIS...UNION...VANDALIA
350 PM CST FRI FEB 28 2014

...WINTER STORM WATCH REMAINS IN EFFECT FROM SATURDAY EVENING
THROUGH LATE SUNDAY NIGHT...

* TIMING...WINTRY MIX WILL BEGIN SATURDAY NIGHT AND CONTINUE INTO
  SUNDAY...BEFORE CHANGING OVER TO ALL SNOW BY SUNDAY EVENING.

* ACCUMULATIONS...SNOW AND SLEET ACCUMULATIONS OF 5 TO 9
  INCHES...ALONG WITH ICE ACCUMULATIONS OF UP TO ONE TENTH OF AN
  INCH.

* WINDS...NORTH 10 TO 15 MPH WITH GUSTS UP TO 20 MPH.

* IMPACTS...SNOW...SLEET AND ICE ACCUMULATION WILL CREATE 
  HAZARDOUS TRAVEL CONDITIONS SATURDAY NIGHT THROUGH SUNDAY 
  NIGHT ACROSS CENTRAL AND EAST CENTRAL MISSOURI AS WELL AS 
  SOUTHWESTERN ILLINOIS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WATCH IS ADVANCED NOTICE THAT SEVERE WINTER
WEATHER IS POSSIBLE IN THE WATCH AREA...IT DOES NOT MEAN IT IS A
CERTAINTY. THOSE IN THE WATCH AREA SHOULD BEGIN PREPARING IN CASE
THE STORM DOES MATERIALIZE. IF YOU HAVE TRAVEL PLANNED...YOU MAY
WANT TO ADJUST YOUR TRAVEL TIME TO AVOID THE STORM. ALSO...YOU
SHOULD USE THIS ADVANCED NOTICE TO MAKE CERTAIN YOUR VEHICLE IS
WINTERIZED. MAKE PREPARATIONS AT HOME BY STOCKING EMERGENCY
SUPPLIES...SUCH AS FOOD...MEDICINE...AND EXTRA HEATING FUEL...
JUST IN CASE THE STORM MAKES TRAVEL IMPOSSIBLE. THIS IS
ESPECIALLY IMPORTANT FOR THOSE LIVING IN RURAL AREAS.

&&

$$

ILZ069-070-074-079-101-102-MOZ065-072>075-084-085-099-011000-
/O.CON.KLSX.WS.A.0003.140302T0000Z-140303T1200Z/
CLINTON IL-CRAWFORD MO-IRON MO-JEFFERSON MO-MADISON MO-MARION IL-
MONROE IL-RANDOLPH IL-REYNOLDS MO-ST. CLAIR IL-ST. FRANCOIS MO-
STE. GENEVIEVE MO-WASHINGTON IL-WASHINGTON MO-
INCLUDING THE CITIES OF...BELLEVILLE...CHESTER...FARMINGTON...
SALEM
350 PM CST FRI FEB 28 2014

...WINTER STORM WATCH REMAINS IN EFFECT FROM SATURDAY EVENING
THROUGH LATE SUNDAY NIGHT...

* TIMING...FREEZING RAIN AND SLEET TO BEGIN SATURDAY NIGHT AND
  CONTINUE THROUGH SUNDAY...BEFORE CHANGING OVER TO ALL SNOW ON SUNDAY
  EVENING.

* ACCUMULATIONS...SNOW AND SLEET ACCUMULATIONS OF 2 TO 5
  INCHES...ALONG WITH ICE ACCUMULATIONS OF UP TO ONE HALF OF AN
  INCH.

* WINDS...NORTH 5 TO 15 MPH WITH GUSTS UP TO 20 MPH.

* IMPACTS...ICE AND SNOW ACCUMULATION WILL CREATE HAZARDOUS TRAVEL
  CONDITIONS SATURDAY NIGHT THROUGH SUNDAY NIGHT OVER SOUTHEAST
  MISSOURI AND SOUTHERN ILLINOIS. ICE ACCUMULATIONS MAY CAUSE
  DAMAGE TO TREES AND OVERHEAD LINES...AND POWER AND TELEPHONE
  OUTAGES ARE A REAL POSSIBILITY. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WATCH IS ADVANCED NOTICE THAT SEVERE WINTER
WEATHER IS POSSIBLE IN THE WATCH AREA...IT DOES NOT MEAN IT IS A
CERTAINTY. THOSE IN THE WATCH AREA SHOULD BEGIN PREPARING IN CASE
THE STORM DOES MATERIALIZE. IF YOU HAVE TRAVEL PLANNED...YOU MAY
WANT TO ADJUST YOUR TRAVEL TIME TO AVOID THE STORM. ALSO...YOU
SHOULD USE THIS ADVANCED NOTICE TO MAKE CERTAIN YOUR VEHICLE IS
WINTERIZED. MAKE PREPARATIONS AT HOME BY STOCKING EMERGENCY
SUPPLIES...SUCH AS FOOD...MEDICINE...AND EXTRA HEATING FUEL...
JUST IN CASE THE STORM MAKES TRAVEL IMPOSSIBLE. THIS IS
ESPECIALLY IMPORTANT FOR THOSE LIVING IN RURAL AREAS.

&&

$$

TRUETT

398 
WWUS43 KLSX 010938
WSWLSX

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE ST LOUIS MO
338 AM CST SAT MAR 1 2014

...MAJOR WINTER STORM TO AFFECT THE REGION TONIGHT THROUGH
SUNDAY NIGHT...

ILZ095>097-MOZ018-019-026-027-034-035-012200-
/O.UPG.KLSX.WS.A.0003.140302T0000Z-140303T1200Z/
/O.NEW.KLSX.WS.W.0004.140302T0000Z-140303T0600Z/
ADAMS IL-BROWN IL-KNOX MO-LEWIS MO-MARION MO-MONROE MO-PIKE IL-
RALLS MO-SHELBY MO-
INCLUDING THE CITIES OF...HANNIBAL...QUINCY
338 AM CST SAT MAR 1 2014

...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO
MIDNIGHT CST SUNDAY NIGHT...

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A WINTER
STORM WARNING FOR SNOW...WHICH IS IN EFFECT FROM 6 PM THIS
EVENING TO MIDNIGHT CST SUNDAY NIGHT. THE WINTER STORM WATCH IS NO
LONGER IN EFFECT.

* TIMING...SNOW TO MOVE INTO THE AREA TONIGHT...CONTINUE 
  THROUGHOUT THE DAY ON SUNDAY...AND PERSIST THROUGH SUNDAY 
  NIGHT.

* ACCUMULATIONS...SNOW ACCUMULATION OF 7 TO 9 INCHES.

* WINDS...NORTH 10 TO 15 MPH WITH GUSTS UP TO 25 MPH.

* IMPACTS...SNOW ACCUMULATION WILL CREATE HAZARDOUS TRAVEL 
  CONDITIONS TONIGHT THROUGH SUNDAY NIGHT OVER NORTHEAST 
  MISSOURI AND WEST CENTRAL ILLINOIS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS THAT A SIGNIFICANT AMOUNT OF SNOW...
SLEET AND/OR ICE IS EXPECTED OR OCCURRING. STRONG WINDS ARE ALSO
POSSIBLE.

&&

$$

ILZ058>060-098-099-MOZ036-041-042-047-048-050>052-012200-
/O.UPG.KLSX.WS.A.0003.140302T0000Z-140303T1200Z/
/O.NEW.KLSX.WS.W.0004.140302T0000Z-140303T1200Z/
AUDRAIN MO-BOONE MO-CALHOUN IL-CALLAWAY MO-COLE MO-GREENE IL-
JERSEY IL-LINCOLN MO-MACOUPIN IL-MONITEAU MO-MONTGOMERY IL-
MONTGOMERY MO-PIKE MO-
INCLUDING THE CITIES OF...BOWLING GREEN...COLUMBIA...
JEFFERSON CITY...LITCHFIELD...MEXICO
338 AM CST SAT MAR 1 2014

...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO 6 AM
CST MONDAY...

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A WINTER
STORM WARNING FOR SNOW...SLEET AND FREEZING RAIN...WHICH IS IN
EFFECT FROM 6 PM THIS EVENING TO 6 AM CST MONDAY. THE WINTER STORM
WATCH IS NO LONGER IN EFFECT.

* TIMING...A MIX OF FREEZING RAIN AND SLEET WILL BEGIN THIS
  EVENING CHANGING OVER TO A MIX OF SLEET AND SNOW LATE
  TONIGHT...BEFORE CHANGING OVER TO ALL SNOW BY MIDDAY ON SUNDAY.

* ACCUMULATIONS...SNOW AND SLEET ACCUMULATION OF 7 TO 10
  INCHES...ALONG WITH A LIGHT GLAZING OF ICE.

* WINDS...NORTH 10 TO 15 MPH WITH GUSTS UP TO 25 MPH.

* IMPACTS...SNOW...SLEET AND ICE ACCUMULATION WILL CREATE 
  HAZARDOUS TRAVEL CONDITIONS TONIGHT THROUGH SUNDAY 
  NIGHT ACROSS CENTRAL AND EAST CENTRAL MISSOURI AS WELL AS 
  SOUTHWESTERN ILLINOIS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS THAT A SIGNIFICANT AMOUNT OF SNOW...
SLEET AND/OR ICE IS EXPECTED OR OCCURRING. STRONG WINDS ARE ALSO
POSSIBLE.

&&

$$

ILZ064-065-100-MOZ049-059>064-012200-
/O.UPG.KLSX.WS.A.0003.140302T0000Z-140303T1200Z/
/O.NEW.KLSX.WS.W.0004.140302T0000Z-140303T1200Z/
BOND IL-FAYETTE IL-FRANKLIN MO-GASCONADE MO-MADISON IL-OSAGE MO-
ST. CHARLES MO-ST. LOUIS CITY MO-ST. LOUIS MO-WARREN MO-
INCLUDING THE CITIES OF...EDWARDSVILLE...ST CHARLES...ST LOUIS...
UNION...VANDALIA
338 AM CST SAT MAR 1 2014

...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO 6 AM
CST MONDAY...

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A WINTER
STORM WARNING FOR SNOW...SLEET AND FREEZING RAIN...WHICH IS IN
EFFECT FROM 6 PM THIS EVENING TO 6 AM CST MONDAY. THE WINTER STORM
WATCH IS NO LONGER IN EFFECT.

* TIMING...A MIX OF FREEZING RAIN AND SLEET WILL BEGIN THIS
  EVENING CHANGING OVER TO A MIX OF SLEET AND SNOW EARLY SUNDAY
  MORNING...BEFORE CHANGING OVER TO ALL SNOW BY MIDDAY ON SUNDAY.

* ACCUMULATIONS...SNOW AND SLEET ACCUMULATION OF 6 TO 8
  INCHES...ALONG WITH UP TO ONE TENTH OF AN INCH OF ICE.

* WINDS...NORTH 10 TO 15 MPH WITH GUSTS UP TO 25 MPH.

* IMPACTS...SNOW...SLEET AND ICE ACCUMULATION WILL CREATE 
  HAZARDOUS TRAVEL CONDITIONS TONIGHT THROUGH SUNDAY 
  NIGHT ACROSS CENTRAL AND EAST CENTRAL MISSOURI AS WELL AS 
  SOUTHWESTERN ILLINOIS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS THAT A SIGNIFICANT AMOUNT OF SNOW...
SLEET AND/OR ICE IS EXPECTED OR OCCURRING. STRONG WINDS ARE ALSO
POSSIBLE.

&&

$$

ILZ069-070-074-101-102-MOZ065-072-073-012200-
/O.UPG.KLSX.WS.A.0003.140302T0000Z-140303T1200Z/
/O.NEW.KLSX.WS.W.0004.140302T0000Z-140303T1200Z/
CLINTON IL-CRAWFORD MO-JEFFERSON MO-MARION IL-MONROE IL-
ST. CLAIR IL-WASHINGTON IL-WASHINGTON MO-
INCLUDING THE CITIES OF...BELLEVILLE...SALEM
338 AM CST SAT MAR 1 2014

...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO 6 AM
CST MONDAY...

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A WINTER
STORM WARNING FOR SNOW...SLEET AND FREEZING RAIN...WHICH IS IN
EFFECT FROM 6 PM THIS EVENING TO 6 AM CST MONDAY. THE WINTER STORM
WATCH IS NO LONGER IN EFFECT.

* TIMING...FREEZING RAIN AND SLEET TO BEGIN TONIGHT AND CONTINUE
  THROUGH SUNDAY...BEFORE CHANGING OVER TO ALL SNOW SUNDAY
  EVENING.

* ACCUMULATIONS...SNOW AND SLEET ACCUMULATION OF 4 TO 7
  INCHES...ALONG WITH OF ONE TENTH TO TWO TENTHS OF AN INCH OF
  ICE.

* WINDS...NORTH 5 TO 15 MPH WITH GUSTS UP TO 25 MPH.

* IMPACTS...ICE...SLEET AND SNOW ACCUMULATION WILL CREATE HAZARDOUS
  TRAVEL CONDITIONS TONIGHT THROUGH SUNDAY NIGHT OVER SOUTHEAST
  MISSOURI AND SOUTHERN ILLINOIS. ICE ACCUMULATIONS MAY CAUSE
  DAMAGE TO TREES AND OVERHEAD LINES...AND POWER AND TELEPHONE
  OUTAGES ARE A REAL POSSIBILITY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS THAT A SIGNIFICANT AMOUNT OF SNOW...
SLEET AND/OR ICE IS EXPECTED OR OCCURRING. STRONG WINDS ARE ALSO
POSSIBLE.

&&

$$

ILZ079-MOZ074-075-084-085-099-012200-
/O.UPG.KLSX.WS.A.0003.140302T0000Z-140303T1200Z/
/O.NEW.KLSX.WS.W.0004.140302T0000Z-140303T1200Z/
IRON MO-MADISON MO-RANDOLPH IL-REYNOLDS MO-ST. FRANCOIS MO-
STE. GENEVIEVE MO-
INCLUDING THE CITIES OF...CHESTER...FARMINGTON
338 AM CST SAT MAR 1 2014

...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO 6 AM
CST MONDAY...

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A WINTER
STORM WARNING FOR SNOW...SLEET AND FREEZING RAIN...WHICH IS IN
EFFECT FROM 6 PM THIS EVENING TO 6 AM CST MONDAY. THE WINTER STORM
WATCH IS NO LONGER IN EFFECT.

* TIMING...RAIN CHANGING TO FREEZING RAIN THIS EVENING AND
  CONTINUE THROUGH SUNDAY MORNING...BEFORE CHANGING OVER TO A MIX
  OF FREEZING RAIN AND SLEET. EVENTUALLY IT WILL CHANGE OVER TO
  ALL SNOW LATE SUNDAY EVENING.

* ACCUMULATIONS...SNOW AND SLEET ACCUMULATION OF 3 TO 6
  INCHES...ALONG WITH OF TWO TENTHS TO ONE QUARTER OF AN INCH OF
  ICE.

* WINDS...NORTH 5 TO 15 MPH WITH GUSTS UP TO 25 MPH.

* IMPACTS...ICE...SLEET AND SNOW ACCUMULATION WILL CREATE
  HAZARDOUS TRAVEL CONDITIONS TONIGHT THROUGH SUNDAY NIGHT OVER
  SOUTHEAST MISSOURI AND SOUTHERN ILLINOIS. ICE ACCUMULATIONS MAY
  CAUSE DAMAGE TO TREES AND OVERHEAD LINES...AND POWER AND
  TELEPHONE OUTAGES ARE A REAL POSSIBILITY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS THAT A SIGNIFICANT AMOUNT OF SNOW...
SLEET AND/OR ICE IS EXPECTED OR OCCURRING. STRONG WINDS ARE ALSO
POSSIBLE.

&&

$$

BYRD

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1107 PM CST Thu Feb 27 2014

.UPDATE:
Issued at 857 PM CST Thu Feb 27 2014

Surface ridge extending from southeast MN southeast through northwest
OH will shift eastward tonight with the surface wind veering
around to an east southeasterly direction by 12z Friday. Just some
mid-high level clouds tonight.  With warm air advection,
particularly across northeast Missouri and west central Illinois,
along with gradually rising 850 mb temperatures, the surface
temperature drop may slow late tonight and even become nearly
steady in spots. Even so the low temperatures tonight will be
well below normal for late February.

GKS

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 311 PM CST Thu Feb 27 2014

(Tonight)

Quiet night is in store as sfc ridge slides off to the east southeast. Winds
will veer to the east tonight and eventually southeast late as return flow
commences. An increase in mid/high level clouds ahead of next storm system
is also expected. For lows tonight...another unseasonably cold night with
lows in the single digits in teens. Leaned toward warmer MET guidance across
central Missouri where clouds should thicken up quickest and where winds
will strengthen faster. Conversely...cooler MAV guidance was preferred for
eastern sections of the CWFA especially southwest Illinois where winds will
be lighter and skies will be clear longest.

(Friday - Friday night)

Complicated forecast for next storm system Friday/Friday night. Models agree
that a shortwave currently over the Great Basin will move eastward and
shear out a bit as it heads into more confluent flow downstream.
Consequently...at lower levels system undergoes cyclolysis with weakening
WAA/isentropic lift as it begins to affect the CWA. Expect area of
precipitation which should weaken as it heads into south-central and
southeast Missouri. Precipitation type is also a problem as sfc temperatures
are progged to warm up and may lead to rain or a rain/snow mix at the least.
Precipitation type will ultimately depend on intensity of precipitation as
boundary layer will need to wetbulb sufficiently to turn precipitation over
to snow. Elevation may also play a role...as eastern Ozarks may have a bit
of an easier time changing over than nearby lower elevations. A secondary
area of light precipitation may also form along arctic baroclinic zone
and last into Friday night. For snow amounts...did not change too much from
previous forecast with amounts around a half inch or less given low confidence
in how much falls and aforementioned ptype issues. Used an SLR of 6:1 to 8:1
due to warm sfc temperatures and possible mixing. Arctic cold front will head
into northwestern sections of the CWFA late Friday night. Ahead of the
boundary boosted temperatures a bit from previous forecast.

Gosselin

.LONG TERM:  (Friday through Next Thursday)
Issued at 311 PM CST Thu Feb 27 2014

A significant winter storm is possible this weekend with
accumulating snow, sleet, and freezing rain from Saturday night
through Sunday night. The take-home message is to start thinking
now about the impacts of a potential winter storm instead of
focusing on ptype forecast minutiae. The ptype forecast for any
given location will likely change right up until the event based
on new atmospheric observations and future model runs. Instead of
focusing on the ptype particulars, focus instead on the idea that
adverse winter weather conditions could affect a large part of the
region this weekend, and consider how you might alter your plans
if such weather were to occur. Based on coordination with neighboring
offices, we will hold off on any winter headlines to let the next
shift get a better handle on how long the event will last. SPS
has already been sent to highlight the winter storm potential and
explain the ptype uncertainty.

Since there appear to be several forcing mechanisms for ascent
(including strong frontogenetic forcing in different layers over
different locations, RER jet dynamics from the H25 jet over the
Great Lakes, and DCVA ahead of an approaching vort max) as well as
sufficient moisture (PW values at the 75th percentile for Feb and
Mar), I am reasonably confident that precipitation will occur in the
LSX CWA between Saturday night and Sunday night. The primary
forecast issues then become ptypes and amounts.

Friday's system will leave a baroclinic zone draped across the
Plains into the south central and southeast US. The E-W portion of
the baroclinic zone will lift slightly northwards and sharpen
considerably on Saturday due to the following influences: 1) an
Arctic air mass accompanying a 1040+ hPa sfc high pressure center as
it slides from Canada into the Plains states, and 2) the surface
response to an approaching mid/upper disturbance, leading to an
inverted surface trough structure and the associated southerly winds
in TX/LA/AR on the warm side of the boundary. Although the surface
baroclinic zone is only forecast to lift as far north as northern AR
and southern MO, it's the 3D position of the boundary within the
lower troposphere (and its movement over time) that will govern
ptypes with this system, and the H92 and H85 positions of this
boundary are forecast to be north of the surface boundary. In
addition, a developing southwesterly H85 LLJ will transport warmer
air north of the surface boundary on Saturday night.

The T/Td profile resulting from a warm nose aloft and very cold air
at the surface means that most of the CWA (excluding northeast MO
and west central IL) should experience periods of sleet and freezing
rain before a changeover to pure snow by Sunday night. There are
some winter precip scenarios where brief periods of sleet and/or ZR
occur at precip onset due to wet bulb cooling. This is not one of
those scenarios; Bufkit soundings are quite emphatic that sleet
and/or ZR will be the dominant ptypes for most of the event in some
locations. Farther north, it looks like precipitation will fall as
pure snow for nearly all of the event.

In general, we're expecting snow in the northern CWA, a band of
mostly sleet (mixed with snow and ZR at times) across the central
CWA, and freezing rain (mixed with sleet at times) across the far
southern CWA. As colder air filters in to the area on late Sunday
night, ptypes will change over (ZR -> IP, IP -> SN) until only
snow remains. It's not yet clear how long snow will linger on
early Monday morning.

Snow/sleet/ice amounts are always difficult to forecast in these
situations because a fixed amount of liquid water translates to
much more snow than sleet and much more sleet than ice accretion.
As the thermal profile changes at any given location due to
multiple factors, the precipitation types will also change.

ECMWF/GFS both show another system affecting the area during the
middle or end of next week, but confidence is low at this time due
to model disagreements with the placement, amplitude, and timing
of the trough.

Kanofsky

&&

.AVIATION:  (For the 06z TAFs through 06z Friday Night)
Issued at 1056 PM CST Thu Feb 27 2014

Latest model guidance continues to favor dry conditions through at
least 18Z Friday at all of the terminals. Coverage of precipitation
that will be lifting northeastward will be scattered, and may not
even affect airports, so will continue to use VCSH. Have delayed
onset of the precipitation even more based on the latest runs of
the models.  Air temperatures are expected to be above freezing,
so expect this to be mainly a liquid event. However, the
temperature profile in the lower atmosphere is close to freezing,
so it is possible for the precipitation to start or end as snow or
sleet. Conditions are expected to be mainly VFR, though MVFR is
possible with the precipitation, and do expect MVFR conditions to
become widespread close to, and especially after 06Z Friday night.

Specifics for KSTL: Confidence that precipitation will occur at
the airport tomorrow continues to lower based on the latest model
guidance. Delayed onset of the VCSH. Still looks like mainly
liquid at the terminal, but there is a small chance that it could
begin or end as with a mix of snow and sleet. Have higher
confidence that MVFR ceilings will move into the terminal after
06Z.

Britt

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

WFO LSX

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
357 PM CST THU FEB 27 2014

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-281200-
GREENE IL-MACOUPIN IL-MONTGOMERY IL-BOND IL-FAYETTE IL-CLINTON IL-
MARION IL-WASHINGTON IL-RANDOLPH IL-ADAMS IL-BROWN IL-PIKE IL-
CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-KNOX MO-
LEWIS MO-SHELBY MO-MARION MO-MONROE MO-RALLS MO-PIKE MO-BOONE MO-
AUDRAIN MO-MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO-
LINCOLN MO-GASCONADE MO-WARREN MO-ST. CHARLES MO-FRANKLIN MO-
ST. LOUIS MO-ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO-
WASHINGTON MO-ST. FRANCOIS MO-STE. GENEVIEVE MO-IRON MO-
MADISON MO-REYNOLDS MO-
357 PM CST THU FEB 27 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN AND
CENTRAL MISSOURI AS WELL AS WEST CENTRAL AND SOUTHWEST ILLINOIS.

.DAY ONE...TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

SNOW IS LIKELY ACROSS MUCH OF THE REGION ON FRIDAY AND FRIDAY
NIGHT. ONLY LIGHT ACCUMULATIONS ARE EXPECTED...GENERALLY AROUND
ONE HALF INCH OR LESS.

A MORE SIGNIFICANT WINTER STORM IS POSSIBLE THIS WEEKEND. A WINTRY
MIX OF SNOW...SLEET...AND FREEZING RAIN IS LIKELY FROM SATURDAY
NIGHT THROUGH SUNDAY NIGHT. THERE IS STILL A LOT OF UNCERTAINTY
REGARDING PRECIPITATION TYPES AND AMOUNTS. PLEASE REFER TO THE
SPECIAL WEATHER STATEMENT FOR ADDITIONAL INFORMATION ABOUT THIS
POTENTIAL WINTER STORM.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED THROUGH TONIGHT.

KANOFSKY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
958 PM CST THU FEB 27 2014

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-281100-
GREENE IL-MACOUPIN IL-MONTGOMERY IL-BOND IL-FAYETTE IL-CLINTON IL-
MARION IL-WASHINGTON IL-RANDOLPH IL-ADAMS IL-BROWN IL-PIKE IL-
CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-KNOX MO-
LEWIS MO-SHELBY MO-MARION MO-MONROE MO-RALLS MO-PIKE MO-BOONE MO-
AUDRAIN MO-MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO-
LINCOLN MO-GASCONADE MO-WARREN MO-ST. CHARLES MO-FRANKLIN MO-
ST. LOUIS MO-ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO-
WASHINGTON MO-ST. FRANCOIS MO-STE. GENEVIEVE MO-IRON MO-
MADISON MO-REYNOLDS MO-
INCLUDING THE CITIES OF...LITCHFIELD...VANDALIA...SALEM...
CHESTER...QUINCY...EDWARDSVILLE...BELLEVILLE...HANNIBAL...
BOWLING GREEN...COLUMBIA...MEXICO...JEFFERSON CITY...ST CHARLES...
UNION...ST LOUIS...FARMINGTON
958 PM CST THU FEB 27 2014

 ...STRONG WINTER STORM TAKING AIM ON THE CENTRAL U.S. THIS
WEEKEND...

THE LATEST WEATHER FORECAST DATA CONTINUES TO INDICATE THAT A STRONG
WINTER STORM WILL BE IMPACTING THE AREA LATE THIS WEEKEND.  IT NOW
APPEARS THAT WINTRY PRECIPITATION WILL OVERSPREAD THE AREA SATURDAY
NIGHT...AND CONTINUE INTO SUNDAY AND SUNDAY NIGHT...BEFORE WINDING
DOWN EARLY MONDAY.

THIS STORM HAS ALL THE NECESSARY INGREDIENTS TO BE A MAJOR WINTER
WEATHER MAKER.  IN GENERAL...IT APPEARS THAT SIGNIFICANT SNOW
ACCUMULATIONS OF 6 OR MORE INCHES WILL BE POSSIBLE OVER NORTHERN
SECTIONS OF THE FORECAST AREA...WITH A SIGNIFICANT ACCUMULATION OF
FREEZING RAIN...SLEET...AND SNOW POSSIBLE OVER THE SOUTH.

UNFORTUNATELY...THE ONE IMPORTANT UNKNOWN IS THE EXACT
TEMPERATURE PROFILE OF THE ATMOSPHERE LATE IN THE WEEKEND...WHICH
WILL DETERMINE HOW MUCH SNOW...SLEET...AND ICE A SPECIFIC LOCATION
WILL RECEIVE. THIS UNKNOWN MAKES FORECASTING SPECIFIC SNOW AND/OR
ICE AMOUNTS IMPOSSIBLE AT THIS TIME.

WHILE ITS STILL TOO EARLY TO DETERMINE EXACT AMOUNTS OF SNOW OR ICE
OVER A SPECIFIC AREA...THOSE IN OR PLANNING TO TRAVEL THROUGH MISSOURI
AND ILLINOIS SHOULD BE AWARE THAT ADVERSE WINTER WEATHER IS ON THE
WAY...AND CAREFULLY MONITOR LATER FORECASTS AND STATEMENTS
REGARDING THE UPCOMING ONSLAUGHT OF LATE SEASON WINTER WEATHER.

GKS