Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks 
NWS Climate Prediction Center College Park, MD 
300 PM EST Tue January 28 2020 
 
6-10 DAY OUTLOOK FOR FEB 03 - 07 2020 
 
Today's model solutions are in good agreement that a highly amplified 500-hPa  
flow pattern will dominate much of North America during the 6-10 day period. A  
500-hPa trough is predicted over the western Aleutian Islands by all ensemble  
models, as a ridge is predicted to build in amplitude over the North Pacific  
and Gulf of Alaska. As a result downstream troughing and northerly flow is  
predicted across much of the CONUS. The resulting forecast indicates negative  
500-hPa height anomalies over Alaska and across Canada into the central and  
much of eastern CONUS. Positive 500-hPa height anomalies are indicated along  
the Pacific coast of the CONUS, with slightly positive anomalies forecast  
across parts of the Southeastern CONUS.  
 
The 6-10 day temperature outlook relies on the temperature forecasts of both  
the GEFS and ECWMF ensembles, despite significant differences in the  
temperature forecast tools from these two models. Below normal temperatures are  
likely for Northern Alaska, under negative 500-hPa height anomalies, while  
above normal temperatures are likely for parts of the Aleutians and the Alaska  
Panhandle with southerly flow predicted ahead of a mid-level trough. Below  
normal temperatures are also likely for the Pacific Northwest into the Rockies,  
as the circulation pattern favors northerly flow into the western CONUS  
overall. The Canadian and ECMWF model solutions cut off the flow of Arctic air  
from the Eastern CONUS resulting in enhanced probabilities for above normal  
temperatures for the Eastern CONUS, as well as parts of the Southern Plains.  
Probabilities of above normal temperatures over the eastern CONUS are moderated  
by the temperature forecast of the GEFS ensemble mean solution. 
 
Above normal precipitation is most likely for Alaska, ahead of a predicted  
trough over the western Aleutians. Near to below normal precipitation is likely  
over most areas west of the Rocky Mountains, under predicted ridging, while  
troughing over the central CONUS, especially later in the 6-10 day period,  
leads to likely above normal precipitation amounts from the Rockies extending  
to the Northern Plains and parts of the Great Lakes region. Above normal  
precipitation is most likely for much of the southeastern CONUS and the middle  
Atlantic states, while below normal precipitation is likely for areas from the  
Southern Plains to the Central Mississippi Valley, consistent with the  
consolidation tool.  
 
The official 6-10 day 500-hPa height blend consists of 20% of Today's 0z GFS  
Ensemble Mean centered on Day 8, 20% of Today's 6z GFS Ensemble Mean centered  
on Day 8, 20% of Today's GFS Superensemble Mean centered on Day 8, 20% of  
Today's 0z European Ensemble Mean centered on Day 8, and 20% of Yesterday's 12z  
European Ensemble Mean centered on Day 7  
  
 
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: Average, 3 out of 5, due to  
relatively agreement among model circulation forecasts, and good agreement  
among precipitation forecast tools, offset by significant disagreement among  
temperature forecast tools.  
 
8-14 DAY OUTLOOK FOR FEB 05 - 11 2020  
 
The manual 500-hPa height blend of the NCEP GEFS and ECMWF forecasts continues  
to show negative 500-hPa height anomalies over mainland Alaska and the Alaska  
Panhandle. Positive 500-hPa height anomalies are predicted over much of the  
west coast of the CONUS, while negative 500-hPa anomalies are predicted to  
extend over nearly the entire CONUS east of the Rocky Mountains, with the  
exceptions of the Florida Peninsula.  
 
The 8-14 day temperature outlook indicates increasing chances of below normal  
temperatures for most of mainland Alaska in association with negative 500-hPa  
height anomalies. Below normal temperatures are also likely for the western  
CONUS and parts of the Great Lakes region, under predicted northerly flow and  
negative 500-hPa height anomalies. Likely above normal temperatures are  
indicated from the Gulf Coast across parts of the Southeast region and along  
the Atlantic Coast under predicted southerly flow early in the 8-14 day period.  
The reforecast calibration tool from ensemble ECMWF favors above normal  
temperatures for the 8-14 day period over most of the CONUS, while temperature  
forecasts from the GEFS favor likely below normal temperatures over the CONUS.  
 
Above normal precipitation continues to be likely for Alaska and the Rocky  
Mountains eastward to the Central CONUS and the Great Lakes. Above normal  
precipitation is also generally likely from east of the Mississippi River to  
the Atlantic coast, as the trough over the eastern CONUS is predicted to  
amplify. Below normal precipitation is likely for parts of the western CONUS to  
the west of the Rockies  behind the predicted trough axis.  
 
The official 8-14 day 500-hPa height blend consists of: 20% of Today's 0z GFS  
Ensemble Mean centered on Day 11, 20% of Today's 6z GFS Ensemble Mean centered  
on Day 11, 20% of Today's GFS Superensemble Mean centered on Day 11, 20% of  
Today's 0z European Ensemble Mean centered on Day 11, and 20% of Yesterday's  
12z European Ensemble Mean centered on Day 10  
 
 
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: Below average, 2 out of 5, due to  
fair agreement among model circulation forecasts and among the precipitation  
forecast tools, offset by significant disagreement among the temperature  
forecast tools.  
 
FORECASTER: Qin Z 
 
Notes: 
 
 
Automated forecasts are issued on Saturday and Sunday. Occasionally manual  
intervention is necessary to address quality control and consistency issues. In  
these cases, forecasts are manually drawn but a full discussion is not issued. 
 
 
The notation for the categorical forecast indicated on the maps is the same as  
that in the tables: A-above   N-near normal   B-below 
 
 
The temperature map shows regions with > 33% chance of being warmer (orange,  
"A"), colder (blue, "B"), or close to (unshaded, "N"). Historical average  
values for the calendar period of the forecast (dashes, "f").  Labels on the  
shaded lines give the probability (> 33%) of the more likely category (B or A).  
 Probability of N is always < 40%. 
 
 
The precipitation map shows regions with > 33% chance of being wetter (green,  
"A"), drier (tan, "B"), or close to (unshaded, "n"). Historical median values  
for the calendar period of the forecast (dashes, "inches").  Labels on the  
shaded lines give the probability (> 33%) of the more likely category (B or A).  
 Probability of N is always < 40%. 
 
 
In the southwest and other climatologically dry regions - there will be a  
greater than 33.3% chance of no precipitation and occasionally even a normal  
(i.e. Median) value of zero - especially during the dry seasons.  In such cases  
a forecast of near normal is effectively a forecast of little or no  
precipitation. 
 
 
The climate prediction center uses 1981-2010 base period means for  
temperature...precipitation...and 500-hpa heights as reference in the climate  
outlooks. 
 
The next set of long-lead monthly and seasonal outlooks will be released on  
February 20. 
 
 
Analogs to the 5 day mean observed pattern centered 3 days ago (D-3) 
for the region from 20N to 70N latitude and 175E to 60W longitude 
include the 5 day periods centered on the following dates:  
19610204 - 19530207 - 19580115 - 19600203 - 19980211 
 
 
Analogs to the 7 day mean observed pattern centered 4 days ago (D-4) 
for the region from 20N to 70N latitude and 175E to 60W longitude 
include the 7 day periods centered on the following dates:  
19610205 - 19530207 - 19600203 - 19560119 - 19580115 
 
 
6-10 DAY OUTLOOK TABLE 
Outlook for Feb 03 - 07 2020 
 
STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN    
WASHINGTON  B    N     OREGON      B    B     NRN CALIF   N    B      
SRN CALIF   N    B     IDAHO       B    A     NEVADA      N    B      
W MONTANA   B    A     E MONTANA   N    A     WYOMING     B    A      
UTAH        B    N     ARIZONA     B    N     COLORADO    B    A      
NEW MEXICO  B    A     N DAKOTA    N    A     S DAKOTA    N    A      
NEBRASKA    N    A     KANSAS      N    B     OKLAHOMA    N    B      
N TEXAS     N    B     S TEXAS     A    B     W TEXAS     N    A      
MINNESOTA   N    A     IOWA        N    B     MISSOURI    N    B      
ARKANSAS    N    B     LOUISIANA   A    A     WISCONSIN   N    A      
ILLINOIS    N    B     MISSISSIPPI A    A     MICHIGAN    A    A      
INDIANA     A    N     OHIO        A    N     KENTUCKY    A    N      
TENNESSEE   A    A     ALABAMA     A    A     NEW YORK    A    N      
VERMONT     A    N     NEW HAMP    A    N     MAINE       A    N      
MASS        A    N     CONN        A    N     RHODE IS    A    N      
PENN        A    N     NEW JERSEY  A    N     W VIRGINIA  A    N      
MARYLAND    A    N     DELAWARE    A    N     VIRGINIA    A    A      
N CAROLINA  A    A     S CAROLINA  A    A     GEORGIA     A    A      
FL PNHDL    A    A     FL PENIN    A    A     AK N SLOPE  B    A      
AK ALEUTIAN N    A     AK WESTERN  B    A     AK INT BSN  B    A      
AK S INT    N    A     AK SO COAST N    A     AK PNHDL    A    A      
  
                            
 
8-14 DAY OUTLOOK TABLE 
Outlook for Feb 05 - 11 2020 
 
STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN    
WASHINGTON  B    N     OREGON      B    B     NRN CALIF   B    B      
SRN CALIF   B    B     IDAHO       B    A     NEVADA      B    B      
W MONTANA   B    A     E MONTANA   N    A     WYOMING     B    A      
UTAH        B    N     ARIZONA     B    A     COLORADO    B    A      
NEW MEXICO  B    A     N DAKOTA    N    A     S DAKOTA    N    A      
NEBRASKA    N    A     KANSAS      N    A     OKLAHOMA    N    N      
N TEXAS     N    N     S TEXAS     A    N     W TEXAS     N    A      
MINNESOTA   B    A     IOWA        B    A     MISSOURI    N    N      
ARKANSAS    N    N     LOUISIANA   A    N     WISCONSIN   B    A      
ILLINOIS    N    N     MISSISSIPPI A    A     MICHIGAN    B    A      
INDIANA     N    N     OHIO        N    N     KENTUCKY    N    N      
TENNESSEE   N    A     ALABAMA     A    A     NEW YORK    N    A      
VERMONT     N    A     NEW HAMP    N    A     MAINE       N    A      
MASS        A    A     CONN        A    A     RHODE IS    A    A      
PENN        N    A     NEW JERSEY  N    A     W VIRGINIA  N    A      
MARYLAND    N    A     DELAWARE    A    A     VIRGINIA    N    A      
N CAROLINA  A    A     S CAROLINA  A    A     GEORGIA     A    A      
FL PNHDL    A    A     FL PENIN    A    A     AK N SLOPE  B    A      
AK ALEUTIAN N    N     AK WESTERN  B    A     AK INT BSN  B    A      
AK S INT    B    A     AK SO COAST B    A     AK PNHDL    B    A      
  
                           LEGEND 
TEMPS WITH RESPECT TO NORMAL     PCPN WITH RESPECT TO MEDIAN 
A - ABOVE   N  - NEAR NORMAL     A - ABOVE   N - NEAR MEDIAN 
B - BELOW                        B - BELOW 
  
THE FORECAST CLASSES REPRESENT AVERAGES FOR EACH STATE. NORMAL 
VALUES - WHICH MAY VARY WIDELY ACROSS SOME STATES - ARE 
AVAILABLE FROM YOUR LOCAL WEATHER SERVICE FORECAST OFFICE. 
  
FOR ADDITIONAL INFORMATION SEE MESSAGE FXUS06 KWBC - ON AWIPS AS 
PMDMRD. 
 
$$