Influence of MJO Could Inspire Much Wetter Texas Forecast in 11-15 Days

Highlight: The West Vs. The East Storm Track for the Next 15 Days

Fig. 1-3: The 12Z GFS percent of normal precipitation 15-day forecast for the East U.S. in 5-day increments based on the 12Z GFS.

Discussion: The 12Z GFS indicates slowly departing heavy rain in the Northeast Gulf States by later tomorrow followed by another event later this week likely featuring significant snow in South Dakota to Minnesota and a severe weather outbreak by Friday in the East-central U.S. (Fig. 1). Similarly, the 6-10-day forecast indicates another piling snowfall across the Upper Midwest while severe weather strikes the Tennessee Valley and vicinity (Fig. 2). In the 11-15-day period, wet weather emerges in the Gulf States possibly related to an MJO-induced moisture feed from the subtropics (Fig. 3). Note the wetter/cooler change for ERCOT!

In the West, another Pacific storm batters California this week with inland mountain snows extending to the Rockies (Fig. 4). In the 6-10-day period, central and southern portions of California receive a break in the rainfall although another storm lurks just offshore (Fig. 5). In the extended range, the West Coast storminess focus is on Oregon and Washington and less so California (Fig. 6).

Fig. 4-6: The 12Z GFS percent of normal precipitation 15-day forecast for the West U.S. in 5-day increments based on the 12Z GFS.

The 12Z GFS indicates a somewhat cooler change in the extended range. Consequently, the April 7-13 U.S. gas population weight HDD forecast is somewhat cooler (Table 1).

Table 1: The 12Z GFS U.S. gas population weight HDD forecast compared to 12 and 24 hours ago.