000
FXUS63 KOAX 012318
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
518 PM CST SUN MAR 1 2015

.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 313 PM CST SUN MAR 1 2015

POTENTIAL MIXED PRECIPITATION EVENT WITH STRONG STORM SYSTEM MONDAY
NIGHT INTO TUESDAY REMAINS THE FOCUS OF THIS FORECAST.

RATHER TRANQUIL WEATHER HAS OVERSPREAD THE AREA THIS AFTERNOON.
PLENTY OF SUNSHINE AND DECENT MIXING WITH WEST TO NORTHWEST WINDS
HAVE PUSHED TEMPERATURES WELL INTO THE 30S. SURFACE HIGH PRESSURE
SETTLING INTO THE REGION TONIGHT WILL ALLOW TEMPS TO DROP BACK INTO
THE TEENS BEFORE WINDS TURN SOUTHERLY AND CLOUDS INCREASE AHEAD OF
EJECTING SHORTWAVE FROM THE SOUTHWEST.

THIS SHORTWAVE COULD TRIGGER A FEW AREAS OF LIGHT SNOW IN NORTHEAST
NEBRASKA MONDAY AFTERNOON WHERE MID LEVEL WARM ADVECTION IS REALIZED
IN SHORTWAVE RIDGING REGIME. INCREASING CLOUDS MAY LIMIT
WARMING...BUT SOUTHERLY FLOW SHOULD HELP HIGHS AGAIN REACH THE 30S
ACROSS THE CWA.

THEN WE TURN TO TUESDAY SYSTEM. TREND OF MODELS OVER THE LAST DAY OR
SO HAS BEEN TO AMPLIFY AFFECT OF NORTHERN STREAM TROUGH SWINGING
THROUGH THE PLAINS WHILE DAMPENING AFFECT OF SOUTHERN STREAM
SHORTWAVE EJECTING FROM UPPER LOW OFF CALIFORNIA COAST. NET RESULT
APPEARS TO BE A MORE NORTHERN TRACK TO SURFACE LOW THROUGH EASTERN
NEBRASKA ON TUESDAY...SHIFTING RAIN/FREEZING RAIN/SNOW LINE
NORTHWARD AS WELL. ALSO...A MORE SIGNIFICANT DRY SLOT WILL LIKELY
LIMIT PRECIPITATION IN SOUTHEAST NEBRASKA. AND SPEED OF SYSTEM
SHOULD LIMIT THE MORE SIGNIFICANT PRECIPITATION TO TUESDAY
MORNING...WITH MOST OF THE AFTERNOON DRY.

STRONG CYCLOGENESIS WILL COMMENCE MONDAY NIGHT IN NORTHEAST COLORADO
WITH SURFACE LOW EJECTING INTO NORTHERN KANSAS OR SOUTH CENTRAL
NEBRASKA OVERNIGHT. STRONG ISENTROPIC UPGLIDE AHEAD OF THE LOW WILL
LEAD TO INCREASING PRECIPITATION CHANCES TOWARD MIDNIGHT ACROSS ALL
OF THE CWA...WITH GREATEST POTENTIAL COMING AFTER MIDNIGHT AS LOW
ENTERS THE PLAINS. FORECAST SOUNDINGS SHOW A LOW LEVEL MOIST LAYER
UNDER INCREASING LIFT...SUGGESTING A LIKELY DRIZZLE SCENARIO IN MUCH
OF OUR AREA MONDAY EVENING. TEMPERATURES AT THIS TIME WILL LIKELY BE
BELOW FREEZING...BUT ROBUST MOISTURE INFUSION WILL PUSH TEMPS ABOVE
FREEZING NEAR AND SOUTH OF INTERSTATE 80 BY MIDNIGHT...
CORRESPONDING TO LIKELY ORIENTATION OF WARM FRONT. CONTINUED THETA-E
ADVECTION OVERNIGHT WILL LEAD TO EXPANSION IN COVERAGE AND INTENSITY
OF PRECIP...ESPECIALLY NORTH OF WARM FRONT. SOUNDINGS HERE SHOW A
SWATH OF MIXED PRECIPITATION IS POSSIBLE FROM FREEZING RAIN TO SLEET
AND SNOW EXTENDING FROM WEST CENTRAL IOWA INTO SOUTHERN PARTS OF
NORTHEAST NEBRASKA. FARTHER NORTH SUFFICIENT DEPTH OF COLD LAYER
POINTS TO ALL SNOW. SURFACE LOW WILL MOVE QUICKLY INTO WESTERN IOWA
EARLY TUESDAY...THEN INTO EASTERN IOWA BY 18Z. STRONG COLD ADVECTION
ON BACK SIDE WILL SWITCH ALL PRECIP TYPES TO SNOW RATHER
QUICKLY...BUT WILL ALSO DRAG PRECIPITATION TO THE EAST QUICKLY AS
WELL.

SO UPSHOT OF THE ABOVE POINTS TO A PERIOD OF POTENTIAL FREEZING
DRIZZLE/RAIN ALONG AND SOUTH OF I-80 THROUGH ABOUT 06Z...BEFORE RAIN
IS THE MOST LIKELY PRECIP TYPE. A COUPLE OF COUNTIES NORTH OF THE
INTERSTATE WILL SEE A MIXED BAG OF PRECIP...AND COULD SEE A FEW
HUNDREDTHS OF AN INCH OF ICE BEFORE CHANGING TO ALL SNOW IN THE
MORNING. FARTHER NORTH...SAY ALONG AND NORTH OF NELIGH TO WAYNE
LINE...MAINLY SNOW IS FORECAST WITH DURATION OF SNOW LEADING TO
AMOUNTS OF 1 TO 3 INCHES. SOME ACCUMULATION OF SNOW SOUTH OF THIS
LINE IS LIKELY TUESDAY MORNING...BUT WILL BE LIMITED AS PRECIP ENDS
SHORTLY AFTER THE CHANGE TO ALL SNOW IS REALIZED.

STRONG NORTH WINDS WILL FOLLOW SYSTEM TUESDAY AFTERNOON WITH
TEMPERATURES FALLING INTO THE TEENS AND 20S BY LATE IN THE DAY. A
WEAK SHORTWAVE DROPPING INTO CENTRAL NEBRASKA COULD SQUEEZE OUT
LIGHT SNOW OR FLURRIES IN OUR WEST TUESDAY NIGHT. OTHERWISE LOWS IN
THE SINGLE DIGITS FOLLOWED BY COOL HIGHS IN TEENS AND 20S ARE
EXPECTED INTO WEDNESDAY.

.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 313 PM CST SUN MAR 1 2015

THE LONGER TERM PERIOD STILL LOOKS DRY WITH A GRADUAL WARMING TREND.
NORTHERN STREAM TROUGH WILL ROTATE TO AND OFF THE EAST COAST WHILE
SLOWLY RISING HEIGHTS ARE FORECAST IN THE PLAINS. AFTER SURFACE HIGH
PRESSURE MOVES EAST OF OUR AREA THURSDAY MORNING...MILD SOUTHWEST
LOW LEVEL FLOW IS FORECAST INTO FRIDAY BEFORE ANOTHER WEAK BOUNDARY
SETTLES INTO THE PLAINS. TEMPERATURES IN THE 30S THURSDAY SHOULD
RISE WELL INTO THE 40S FRIDAY AND CONTINUE THROUGH THE WEEKEND.

&&

.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 516 PM CST SUN MAR 1 2015

VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. WINDS WILL BECOME
LIGHT AND VARIABLE THIS EVENING..BUT BECOME SOUTHEAST ON MON AND
INCREASE THROUGH THE DAY WITH SPEEDS AOA 12 KT WITH GUSTS OVER 20
KT LIKELY AT ALL 3 SITES. WE WILL ALSO SEE AN INCREASE IN MID AND
HIGH LEVEL CLOUDS DURING THE DAY ON MON.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.

&&

$$

SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...BOUSTEAD