Watts, Oklahoma

... Severe Thunderstorm Warning criterion for hail changing...

To: subscribers: NWS partners... users and employees

Subject: National change in minimum hail size criterion
          for issuing Severe Thunderstorm Warning /svr/
          and severe weather statement /svs/ products
          effective January 5 2010

Effective Tuesday January 5 2010 at 0001 coordinated Universal time
/UTC/... 601 PM CST January 4 2010... all NWS weather forecast offices
/wfos/ will operationally change the minimum hail size criterion
used to issue Severe Thunderstorm Warning /svr/ and severe weather
statement /svs/ products from 3/4 inch /penny/ diameter or larger
hail to 1 inch /quarter/ diameter or larger hail.

No change is being made to the svr and svs product wind criterion
of wind gusts equal to or in excess of 50 knots /58 mph/.

A public information statement /pns/ soliciting comments regarding
this change was issued September 23 2009 /use lowercase/:

Http://www.Weather.Gov/os/notification/pns09_1_inch_hail.Txt

NWS received 63 comments in response to the pns... 54 of which /86
percent/ supported this change. A web Page was created to address
some of the comments... which indicated more education and outreach
was needed. The webpage can be found at /use lower case/...
http://www.Weather.Gov/oneinchhail

NWS reviewed all comments before deciding to change minimum hail
size criterion for svr and svs products.

Central and western region wfos currently issue svr and svs
products experimentally using the 1 inch /quarter/ diameter or
larger hail size criterion /use lower case/:

Http://www.NWS.NOAA.Gov/om/notification/scn09-19hail_change.Txt

And

Http://www.NWS.NOAA.Gov/om/notification/scn09-36wr_hail_exp.Txt

These wfos will continue to issue 1 inch /quarter/ hail size
criterion products experimentally through January 4 2010. All NWS
wfos will adopt the new criterion operationally on January 5 2010.

For further information regarding this change please contact:

John T ferree
fire and public weather services branch
120 David l. Boren Blvd
suite 2312
Norman OK 73072
405-325-2209
John.T.Ferree@noaa.Gov

Or

Ed calianese
warning coordination meteorologist
National Weather Service Tulsa OK
10159 E 11th St suite 300
Tulsa OK 74128
918-838-7838
ed.Calianese@noaa.Gov

National service change notices are online at /use lowercase/:

Http://www.Weather.Gov/os/notif.Htm