Effective November 5, 2008, all TAFs issued by the NWS will change the date and time format in the TAF from the present 24 hour format to a new 30 hour format that is consistent with the International Civil Aviation Organization (ICAO) Rules. This change will occur with the 00Z issuance Nov 5th (6 pm MST on Nov 4th). WFO Pueblo will continue to issue TAFs that forecast for a 24hour forecast period; the only change to the three TAFs issued by WFO PUB (KALS, KPUB, KCOS) will be in the format, to comply with the new international 30 hour format change. The Denver International airport is the only Colorado airport that will be converting to a 30 hour forecast.
Here is an example of the format change, with the changes in large bold:
KPUB 061131Z 061212 VRB06KT P6SM SCT250
FM1900 21015KT P6SM FEW250
FM0000 17010KT P6SM SKC
FM0600 36006KT P6SM BKN050
KPUB 061131Z 0612/0712 VRB06KT P6SM SCT250
FM061900 21015KT P6SM FEW250
FM070000 17010KT P6SM SKC
FM070600 36006KT P6SM BKN050
Note that the only change is in the format to indicate the date as well as time in FM and TEMPO groups.