Climate Prediction Center - Week 3-4 Outlook

Prognostic Discussion for Week 3-4 Temperature and Precipitation Outlooks
NWS Climate Prediction Center College Park MD
300PM EDT Fri Jun 20 2025

Week 3-4 Forecast Discussion Valid Sat Jul 05 2025-Fri Jul 18 2025

Currently, El Niño Southern Oscillation (ENSO) conditions are neutral in the equatorial Pacific Ocean, and sea surface temperatures (SSTs) are near average across much of the tropical Pacific Ocean. The Madden Julian Oscillation (MJO) recently weakened, and GEFS and ECWMF ensemble forecasts of the realtime multivariate MJO (RMM) index do not depict a meaningful MJO signal during the next two weeks. The weakness of these drivers in this week's forecast is similar to last week, and as such the main components of the forecast remain similar as well. We consider dynamical model forecasts of temperature and precipitation from the ECMWF, GEFS, JMA, and CFSv2 models and various blends of these 4 models, evolution of the pattern from the current week 2 forecast, soil moisture influence on local temperature and precipitation, and coastal SST anomalies. The multivariate linear regression (MLR) based on MJO, ENSO, and trend was not used in today’s outlook except to estimate the potential influence of trend on temperature and precipitation.

500-hPa height forecasts from GEFS, ECMWF, CFS, and JMA depict troughing over Alaska, with some differences in trough placement and strength between models. For example, CFS has the trough placed more over the northern coast, while ECMWF has the trough over the more central part of the state. Ridging is present in the models off the southern coast of Alaska. Over the Contiguous United States (CONUS), anomalous ridging and positive height anomalies are forecast over the northern tier, transitioning to weakly above normal or neutral heights over the Southeast and parts of the Mid-Atlantic. Ridging is strongest, and generally most consistent among models, over the Northwest and New England.

The Weeks 3-4 Temperature Outlook favors below normal temperatures over southwestern Alaska, associated with favored troughing, and consistent with dynamical model temperature forecasts. Temperature probabilities transition to equal chances (EC) of above and below normal temperatures over the northern part of Alaska where model uncertainty was higher. Similarly to last week, above normal temperatures are favored across almost the entire CONUS. Probabilities of above normal temperatures are the highest, reaching 70 to 80 percent, over parts of the West and New England where ridging is favored to be stronger, there was agreement among models, and temperature trends are above normal. Probabilities are weaker, reaching EC, over the Gulf States and parts of the Southeast where above normal precipitation is favored and soil moisture has been high. Probabilities are also slightly moderated just south of the Great Lakes where trends are weaker. While enhanced above normal probabilities are forecast over the West Coast and southern New England Coast, probabilities are comparatively weaker than those found more in-land, given cooler SSTs and possibility of local sea breezes that may have a cooling effect.

The Weeks 3-4 Precipitation Forecast is also similar to last week's forecast, with some minor changes to reflect updated guidance. Above median precipitation is forecast for southern and central Alaska, consistent with forecasted troughing. Below median precipitation is favored over the Northwest and North-Central CONUS, beneath predicted ridging and where dynamical models were consistent. A slight tilt toward below median precipitation is also favored over southern Texas and southern Florida given agreement among the models. Above median precipitation is favored for the Southwest, which is one of the stronger and more consistent signals that is seen across the models given the possibility of enhanced moisture flow into the western CONUS. However, there are some differences in the extent of the above median precipitation over the Southwest in the models, thus probabilities are highest reflecting the area of best agreement. Above median precipitation is also indicated for the Southeast and parts of the Mid-Atlantic given favored probabilities for above median precipitation among all available models. EC for above and below median precipitation is forecast for the remainder of the CONUS where model signals were weak or inconsistent.

Probabilities for above normal temperatures remain elevated over Hawaii given above average sea surface temperatures and ridging. Slightly enhanced probabilities of above median precipitation are indicated over Hawaii by dynamical models, with EC favored over Hilo given disagreement among models.

Temperature Precipitation

FCST FCST

Hilo A60 EC

Kahului A70 A55

Honolulu A70 A55

Lihue A70 A55

Forecaster: Johnna Infanti

The next week 3-4 outlook will be issued on Friday, Jun 27, 2025

These outlooks are based on departures from the 1991-2020 base period

These are two category outlooks and differ from official current three category outlooks currently used for the monthly and seasonal forecasts.

The shading on the temperature map depicts the most favored category, either above-normal (A) or below-normal (B) with the solid lines giving the probability ( >50%) of this more likely category (above or below).

The shading on the precipitation map depicts the most favored category, either above-median (A) or below-median (B) with the solid lines giving the probability ( >50%) of this more likely category (above or below).

In areas where the likelihoods of 2-week mean temperatures and accumulated precipitation amounts are similar to climatological probabilities, equal chances (EC) is indicated.