Arctic Cold Front Impacting the Great Lakes into the Northeast

A powerful Arctic cold front will sweep across the Great Lakes today and into the Northeast early Thursday. Expect brief, intense bursts of heavy snowfall and gusty winds. Widespread strong winds will spread from the Northern Plains to the Great Lakes today and reach the Central Appalachians, Mid-Atlantic, and Northeast by Thursday, where some blizzard conditions are expected in the Appalachians. Read More >

Table C5

Reference Time designator A2

(when T1 = Q, X, or Y)

Instructions for the proper application of the reference time designator

1. The designator specified in this table should be used to the greatest extent possible to indicate the reference time of data contained within the text of the bulletin.

2. When the table does not contain a suitable designator for the reference time, an alphabetic designator which is not assigned in the table should be introduced and the WMO secretariat notified.

Designator	Data Type	Designator	Data Type
A	Analysis (00 hour)	N	39 hours forecast
B	3 hours forecast	O	42 hours forecast
C	6 hours forecast	P	45 hours forecast
D	9 hours forecasts	Q	48 hours forecast
E	12 hours forecast	R	54 hours forecast [48+6]
F	15 hours forecast	S	66 hours forecast [+12]
G	18 hours forecast	T	78 hours forecast
H	21 hours forecast	U	90 hours forecast
I	24 hours forecast	V	102 days forecast
J	27 hours forecast	W	114 days forecast
K	30 hours forecast	X	126 days forecast
L	33 hours forecast	Y	138 days forecast
M	36 hours forecast	Z	150 days forecast