EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1140 PM EST FRI JAN 30 2015

VALID 12Z TUE FEB 03 2015 - 12Z SAT FEB 07 2015


THE GLOBAL NUMERICAL MODELS ARE INDICATING A SLIGHT PROGRESSION OF
THE LONGWAVES ACROSS CENTRAL NORTH AMERICA AT THE MEDIUM RANGE,
WITH THE PACIFIC TROUGH EDGING ACROSS THE WEST COAST AND THE BROAD
TROUGH OVER THE EAST INCHING TOWARD THE ATLANTIC. PLENTY OF COLD
AIR IS PROGGED TO CHILL MUCH OF THE EAST, WITH THE LARGEST
DEPARTURES FROM NORMAL ON THE POLEWARD SIDE OF 40N. IT COULD DIP
TO ZERO FAHRENHEIT AS FAR SOUTH AS THE OLD MASON-DIXON LINE ON
TUESDAY MORNING IN THE WAKE OF THE SHORT-RANGE WINTER-WEATHER
PRODUCER. USED MORE OF THE NAEFS MEAN THAN THE ECENS MEAN IN THIS
PACKAGE BASED ON RECENT PERFORMANCE OF THOSE BROAD,
ARITHMETICALLY-AVERAGED GUIDANCE TOOLS. THE NAEFS HAS MORE MEMBERS
WITH ONE LAST WAVE SCOOTING ACROSS THE SOUTHEAST LATE IN THE
PERIOD--BEFORE THE SLIGHT PROGRESSION OF THE FLOW DISCOURAGES A
SIGNIFICANT INFLUX OF ATLANTIC MOISTURE. THE TROUGH EDGING INTO
THE WEST COAST SHOULD BE MARKED BY A SIGNIFICANT UPTICK IN
PRECIPITATION FROM ABOUT SAN FRANCISCO NORTHWARD, WITH A SLOW,
INLAND CREEP OF THE MOISTURE WITH TIME.


CISCO