Long Range Weather Forecast Discussion April 28-May 12
1625 PM EDT Thu. Apr. 25, 2024Apr. 28-May 2: A trough is forecast in the West with a ridge across eastern North America and Greenland.
Low pressure will track northeast across the central Plains and will bring severe storms from the central Plains eastward to the lower to mid-Mississippi Valley into Monday. A strong trough will push through the Northwest and reach the northern Plains. A low-level southerly flow from the Gulf will transport moisture across the southern Plains leading to rain and storms.
May 3-7: The flow does not change very much during this period with a trough over the Northwest and above normal heights across much of Canada and the East.
TEMPERATURES
Below-normal temperatures are forecast for the West Coast. Anomalies of 4°F are possible. Above-normal temperatures are forecast for most of the Rockies to the Atlantic Coast. Anomalies are expected to be near 6°F.
Yellow-2-4°F
Orange-4-6°F
Red-6-8°F or Greater
Mediam Blue 4-6F Below
Dark Blue-6-8F or Great Below
PRECIPITATION
Yellow=-35%
Below
Brown-35-45% Below
Dark
Brown-45-55% Below
Light
Green-30-35% Above
Green-35-45% Above
Dark
Green-45-55%Above
Above-normal precipitation is forecast for the West Coast. The probability of occurrence is near 35 percent. Below-normal precipitation is forecast for the northern Rockies and east of the Plains to the Atlantic Coast. The probability of occurrence is near 35 percent.
May 8-12: The flow is a little more flatter compared to the previous period. The height anomalies remain pretty much the same with a trough in the West and a ridge in the East. The GFS has a trough in the East. The ECMWF weeklies have the eastern trough further east.
TEMPERATURES
Yeloow-2-4°F
Orange-4-6°F
Red-6-8°F or Greater
Medium Blue-4-6F Below
Dark Blue-6-8F or Great Below