Moderate La Nina According to Multivariate ENSO Index But Weakening Expected

Fig. 1-2: The NOAA/WPC 1-2-day precipitation forecast for the U.S. plus early next week.

Discussion: High impact weather is somewhat confined to the Mid-south States this week and next week due to heavy rainfall episodes. In the short-term, an area of heavy rain including strong thunderstorms on the Texas Coast emerges today and expands to the Mid-south U.S. tonight and Wednesday, including severe storms centered on Louisiana. The 2-day rainfall indicates several inches of rain (Fig. 1) causing more flooding across the area hit hard by last week’s ice storm in eastern Oklahoma and Arkansas. Another storm similar in aerial coverage and intensity emerges early next week for the same area (Fig. 2). Each area of heavy rain shifts east through the Southeast States but loses intensity.

Regarding ENSO, the latest monthly multivariate ENSO index is -1.1 which indicates a moderate-strength La Nina remains in-place. However, as La Nina enters a 4^th year, the MEI observations are following the analog of 3 previous lengthy La Nina episodes and slowly weakening on the way toward El Nino by mid-year (Fig. 3).

The latest U.S. gas population weigh HDD forecast reveals a much warmer Feb. 10-16 forecast change followed by a return to near normal national heating demand the following week (Fig. 4).

Fig. 3: Multivariate ENSO index for DEC/JAN was -1.1 which matches the MEI analog forecast for 2023 so far.

Fig. 4: The gas population weight HDD forecast using all models, their consensus and compared to 48 hours ago plus the 10-day/30-day normal.