Information Shown on Composite Weather Maps:
Composite weather maps showing an overview of the West Coast of North
America are generated three times daily (for 00Z and 12Z, the latter
replaced later by 18Z, overlaying visible satellite images) or four
times daily (for 00Z, 06Z, 12Z, and 18Z overlaying infrared satellite
images). They display the following information:
West Coast Overview
- (1) Contours of sea-level pressure (at intervals
of 4 millibars).
The analyses come from the eta-model initialization (00Z and 12Z maps)
or the meso-eta-model initialization (6Z and 18Z maps), each performed
twice daily by the National Centers for Environmental Prediction
(NCEP--formerly the National Meteorological Center, NMC);
- (2) Either a visible or a color-enhanced infrared
satellite image from the GOES-West satellite, usually recorded at the
same time as the analyses in (1) above (except for the visible
image for the 12Z map, which is too early--instead, a 14Z or 15Z image
is used with the 12Z analysis, which is later replaced by an 18Z image
and analysis when they become available); and
- (3) Plots of surface winds and cloud cover
recorded at the same time as the satellite image in (2) above. The wind
- wind speed (in knots); and
- wind direction.
The time and date appearing on these maps is in Universal
Time Coordinates (UTC), formerly known as Greenwich Mean Time (GMT).
comments about time labels
for more information.)
For information about reading some of the meteorological information
on these maps, refer to the
key to weather-station plots
general description of visible and infrared satellite images.