National Weather Service Burlington, VT NWS Burlington 2013-14 Winter Weather Workshop Scott Whittier - WCM

National Weather ServiceNational Weather ServiceBurlington, VTBurlington, VT

NWS Burlington 2013-14 Winter Weather Workshop

Scott Whittier - WCM

Outline

• Verification 2012-13– More active than 2011-12– Still below normal– 5 Year Running averages

• Review WSW/NPW policy– Philosophy– Software restrictions

• IDSS


ER Verification Winter Storm Total Events

1334 events616 events

2011-122012-2013

Busier, but still below average ~100



NWS BTV Winter Verification History


ER Verification Probability of Detection (POD)

2012-2013 2011-2012


ER Verification False Alarm Ratio (FAR)

2012-2013 2011-2012


ER Verification Winter Storm Average Lead Time

2012-2013 2011-2012

ER Verification Overall GPRA/GPRA+ Rankings

2012-2013


ER Winter Verification (5 seasons) October 2008 – September 2013


ER Winter Verification (5 seasons)October 2008 – September 2013


ER High Wind VerificationOctober 2012 – September 2013

(SANDY and Nor’Easters)


ER High Wind VerificationOctober 2012 – September 2013

(SANDY and Nor’Easters)


ER High Wind VerificationSandy vs. Post Sandy


ER High Wind Verification (5 seasons) October 2008 – September 2013

Top Locations are Coastal or Great Lakes


ER High Wind Verification (5 seasons) October 2008 – September 2013



Watch/Warning Philosophy• Collaborate with Adjacent WFO’s for “consistent, uniform message”

– Type of Hazard, Start and Stop Times, Accumulations• Most Cases…ALY/BUF (Same or Earlier Start/Stop), GYX (Same or Later)

• Make “Liberal” Start / End Times (esp Watches)– Beginning: Start of Snow/Winter Pcpn– End: Several hours AFTER expected end of Accumulating Snow

• “When In Doubt…Stretch it Out”

• Watches should be more Liberal than Warnings– Due to Greater uncertainty (Track and Time)

• Warnings should be shorter– More likely at the beginning due to closer proximity to start time



• CAREFUL when Alternating Start/Stop times – “Technically” creates a new “Verification” warning and Lead Time clock– Previous warning becomes invalid and is a non-verified warning (FAR)– ONLY if you feel Forecast would be a complete BUST and/or unrepresentative!!!

• CAREFUL when re-grouping Hazard Grids… especially BEFORE event begins

– Make sure Valid times are the same as previous WSW/NPW– Avoid the Inadvertent NEW “Verification Warning”

• NEVER adjust VTEC in AWIPS– Close product and Restart in GFE

Adjusting Start/Stop Times and Regrouping Hazard Grids



Frequency of WSW/NPW Issuances• Pre-event issuances

– Once per full package suite or Once per shift• Set Product expiration time no less than ~ 12-14 hours

– More frequent as conditions warrant• Better timing of the arrival of wintry precipitation

• During an Event– Once per shift and/or more frequently (< 6 hours)

• Set Product expiration time ~ 6-8 hours– More frequent as conditions warrant

• Changes to forecast, Timing, Impacts, Validity of forecast– “Rain has already changed to snow, thus heavier snowfall totals expected”– “A heavy snow band with snowfall rates of 1 to 2 inches per hour will impact the

Champlain Valley through 6 pm”– “Snowfall amounts of 12 inches or more have already been observed in southern

Vermont”



Bulleted WSW/NPW Content– Keep wording clear and concise

• Ask yourself... “if it really needs to be in there?”

– Keep Bullets to a few lines of text at most– Bullets should be coherent and end with period

• ACCUMULATIONS… 6 to 12 inches of snow.

– Timing Bullet: DO NOT REGURGITATE HEADLINE!!!• “Value Added” Information• SNOW DEVELOPS THIS AFTERNOON…BECOMING HEAVY AT TIMES

TONIGHT, THEN GRADUALLY ENDING WEDNESDAY MORNING.• WINDS WILL INCREASE THIS MORNING...PEAKING DURING THE

AFTERNOON HOURS TODAY...BEFORE ABATING THIS EVENING.

– Add Bullets as necessary• Multiple Hazards/Impacts• Separate Snow/Ice Accumulations, if two different systems• Observed Snowfall for Validity?

IDSS• Collaboration between forecasters and IDSS person

(Andy, Scott, Designated personnel)– Shift briefing and possibly after 12z guidance

• Attempt to have Headline decisions by 2 pm– Any last minute changes, please pass on to IDSS person

and vice versa (IDSS needs to check with forecaster)

• E-mails by Management or Lead Designee– Weekend/Holiday…need help call Andy or Scott– Midshifts…please consider, especially if there are changes

• Embrace Social Media


Any Questions???

Documents

National Weather Service Burlington, VT NWS Burlington 2013-14 Winter Weather Workshop Scott Whittier - WCM