Fire Weather Outlook Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
000
FNUS21 KWNS 181638
FWDDY1

DAY 1 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1137 AM CDT SAT APR 18 2015

VALID 181700Z - 191200Z

...CRITICAL FIRE WEATHER AREA FOR SOUTHERN NEW MEXICO AND THE
NORTHERN TRANS PECOS...

LATEST OBSERVATIONS SUPPORT THE ONGOING FORECAST. ONLY MINOR CHANGES
HAVE BEEN MADE TO THE ELEVATED AREA OVER NEW ENGLAND.

ACROSS THE SOUTHERN PORTIONS OF THE NORTH EAST UNITED
STATES...OBSERVATIONS INDICATE RELATIVE-HUMIDITY VALUES FALLING INTO
THE 20-40 PERCENT RANGE. ALTHOUGH SURFACE WINDS HAVE REMAINED FAIRLY
LIGHT...THEY ARE EXPECTED TO INCREASE THROUGHOUT THE AFTERNOON ALONG
AND BEHIND AN APPROACHING SURFACE FRONT. THE POTENTIAL FOR
RELATIVELY STRONG SURFACE WINDS/GUSTS ACROSS LONG ISLAND WARRANTS
INCLUSION IN AN ELEVATED AREA...AND THE NECESSARY ADJUSTMENTS HAVE
BEEN MADE.

ELSEWHERE...THE ONGOING FORECAST REMAINS ON TRACK. PLEASE READ THE
DISCUSSION BELOW FOR ADDITIONAL FORECAST INSIGHTS.

..MARSH.. 04/18/2015

.PREV DISCUSSION... /ISSUED 0349 AM CDT SAT APR 18 2015/

...SYNOPSIS...
A MID/UPPER-LEVEL LOW WILL DRIFT EWD FROM CO INTO THE CNTRL
PLAINS...BEFORE BEGINNING TO PHASE WITH A NRN-STREAM PERTURBATION
LATE IN THE PERIOD. ELSEWHERE...A STOUT SHORTWAVE TROUGH WILL
PROGRESS E/SEWD FROM ONTARIO THROUGH NEW ENGLAND AND OFFSHORE THE
ATLANTIC COAST BY THE END OF THE PERIOD.

THE RESULTANT SFC PATTERN WILL FEATURE LOW PRESSURE ACROSS THE SRN
HIGH PLAINS...WITH AN ATTENDANT DRY LINE EXTENDING TO THE SOUTH.
ACROSS THE NORTHEAST...A COLD FRONT WILL MOVE THROUGH THE REGION
LATER IN THE DAY...WITH RIDGING PROGRESSING FROM THE NRN PLAINS/SRN
ONTARIO TOWARDS THE LOWER GREAT LAKES/SERN ONTARIO/QUEBEC.

...PORTIONS OF SRN NM...SERN AZ...WRN TX...
WITH THE CORE OF THE AFOREMENTIONED MID/UPPER LOW REMAINING TO THE
NORTH OF THE REGION...A CORRIDOR OF ENHANCED WLY FLOW ALOFT WILL
REMAIN SITUATED OVER FAR SRN NM AND THE SURROUNDING AREA. WITH THE
ONSET OF DEEP DIURNAL MIXING...WINDS SHOULD INCREASE TO AROUND 20
MPH /WITH HIGHER GUSTS/ AND RH VALUES SHOULD FALL TO AROUND 10-15
PERCENT /ENHANCED IN TERRAIN-FAVORED DOWNSLOPE AREAS/. WHILE THE
REGION HAS EXPERIENCED RAINFALL OVER THE PAST WEEK...THE LATEST
FINE-FUEL GUIDANCE SUGGESTS THEY SHOULD BE RECEPTIVE FOR FIRE
SPREAD. AS SUCH...A CRITICAL DELINEATION HAS BEEN INTRODUCED...WITH
THE PREVIOUS ELEVATED DELINEATION MAINTAINED WITH ONLY MINOR
ADJUSTMENTS.

...PORTIONS OF THE NORTHEAST AND NEW ENGLAND...
WITH THE PASSING SHORTWAVE TROUGH...AN ATTENDANT SFC WAVE AND COLD
FRONT WILL APPROACH THE REGION DURING THE DAY. W/SWLY FLOW AND
RESULTANT DOWNSLOPE TRAJECTORIES WILL COMBINE WITH DIURNAL HEATING
TO PROMOTE A WELL-MIXED BL DURING THE DAY. IN RESPONSE...RH VALUES
WILL FALL INTO THE 25-35 PERCENT RANGE ACROSS MUCH OF THE
REGION...WHILE SUSTAINED WINDS WILL REACH 15-20 MPH BY AFTERNOON.
WINDS WILL THEN VEER TO THE NW AND INCREASE SLIGHTLY FOLLOWING THE
FRONTAL PASSAGE...BUT AS IT LOOKS TO BE LATER IN THE DAY...COOLING
TEMPS WILL FAVOR RISING RH LEVELS BY THIS TIME. AS SUCH...WHILE
LOCALLY CRITICAL CONDITIONS ARE POSSIBLE...CONFIDENCE IN THE
NECESSARY DURATION OF SUCH CONDITIONS IS TOO LOW FOR A CRITICAL
DELINEATION. THEREFORE...THE PREVIOUS ELEVATED AREA WAS MAINTAINED
WITH ONLY SLIGHT ADJUSTMENTS.

...PORTIONS OF CNTRL/SRN WI...
LOCALLY ELEVATED CONDITIONS MAY BE POSSIBLE DURING THE DAY...AS ELY
WINDS INCREASE IN RESPONSE TO A TIGHTENING PRESSURE GRADIENT BETWEEN
HIGH PRESSURE ACROSS THE GREAT LAKES AND TROUGHING ACROSS THE
PLAINS. WITH LOW LEVEL TRAJECTORIES EMANATING FROM THE DRY
RIDGE...RH VALUES MAY FALL TO AROUND 25 PERCENT DURING THE
DAY...WHILE SUSTAINED WINDS REACH AROUND 10-15 MPH. DRY FUELS WILL
SUPPORT AN ENHANCED RISK FOR FIRE SPREAD AS WELL. HOWEVER...DUE TO
THE MARGINAL METEOROLOGICAL CONDITIONS...A DELINEATION WILL NOT BE
INTRODUCED WITH THIS FORECAST. ONE MAY BE REQUIRED WITH THE NEXT
UPDATE THOUGH...IF CONFIDENCE INCREASES IN LOWER RH VALUES/STRONGER
WINDS.

...PORTIONS OF ERN MT...
CONDITIONS MAY BRIEFLY APPROACH/REACH ELEVATED LEVELS AS A COLD
FRONT MOVES ACROSS THE REGION DURING THE DAY. ALTHOUGH WINDS WILL BE
STRONG OUT OF THE NORTH...RH VALUES MAY ONLY BRIEFLY FALL INTO THE
20-25 PERCENT RANGE...AS TEMPS WILL BE SOMEWHAT MARGINAL /GENERALLY
IN THE UPPER 50S-LOWER 60S/. THEREFORE...NO DELINEATION HAS BEEN
INTRODUCED.

...PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT...




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.