Prognostic Discussion for Week 3-4 Temperature and Precipitation Outlooks
NWS Climate Prediction Center College Park MD
300PM EST Fri Nov 14 2025
Week 3-4 Forecast Discussion Valid Sat Nov 29 2025-Fri Dec 12 2025
There are several tropical and extratropical climate signals that could potentially impact the current Week 3-4 forecast, many of which tend to promote colder than normal temperatures for much of the northern tier of the continental United States (CONUS). In the extratropics, the eastward propagation of the Madden Julian Oscillation (MJO) convection is currently in the Western Pacific (RMM Phase 6). It’s likely that the MJO signal will stall in the next week as it interferes with lower-frequency signals, such as La Niña. The current phase of the MJO tends to promote anomalously cold temperatures in the northern and eastern CONUS.
In the extratropics, the negative Arctic Oscillation (AO) that brought cold temperatures to the eastern CONUS in recent weeks has perturbed the stratospheric polar vortex. Some dynamical models indicate a brief major Sudden Stratospheric Warming (SSW) may occur, a rare event in the month of November. If one does transpire and propagates to the troposphere, the AO may continue to remain in the negative phase. However, the current forecasts are mixed on the phase of the AO. The North Pacific Oscillation (NPO) is also trending toward the negative phase, which can give rise to anomalously cold air for the CONUS.
The large-scale atmospheric circulation for the Week 3-4 period is dominated by a wave-train pattern over North America. Above normal height anomalies extend from Alaska down to the California coastline with a broad region of anomalously low heights over the Hudson Bay and the northern CONUS. Weaker positive height anomalies are also indicated over the Southeast. This wave-train pattern is forecast to remain consistent throughout the period but the amplitudes, particularly the positive height anomalies, weaken in Week 4. The majority of the dynamical models capture this pattern, but CFS is the outlier. For that model, the negative height anomalies are confined more to the Great Lakes region and the positive height anomalies are more widespread across the western and southern CONUS. Overall, the wave-train features of the circulation pattern do not project well onto the typical negative AO like response associated with an SSW. Rather, these features tend to align more with a negative NPO as well as the MJO-related teleconnections.
The Week 3-4 Temperature Outlook favors below normal temperatures across the northern tier consistent with MJO and La Niña conditions as well as the negative NPO. Highest probabilities are in the Northern Plains and Upper Great Lakes where the models strongly agree on cold for both Week 3 and Week 4. The cold signal west of the Northern Plains is forecast to be stronger in Week-3 before weakening. Across the Northeast, the temperature anomalies are forecast to be modest during Week-3 before becoming more strongly negative during the second week of the period. Enhanced probabilities of above normal temperatures are highlighted for the Southeast under the anomalous ridging. For the rest of the CONUS, model signals are weaker and mixed. As a result, Equal Chances (EC) of above or below normal temperatures are indicated for much of the western and southern parts of the CONUS.
The Week 3-4 Precipitation Outlook tilts toward above normal precipitation in several parts of the CONUS. First, ahead of the trough axis over the eastern CONUS and Canada, wet conditions are favored for the Ohio and Tennessee Valleys. Second, above normal precipitation is forecast for the Northern and Central Rockies, where model agreement is strong. Elsewhere across the CONUS, weak model signals result in EC of above or below normal precipitation.
While the geopotential height anomalies over Alaska are amplified, the exact location of the axis differs between models leading to overall uncertainty in the temperature and precipitation forecast. Models consistently favor above normal temperatures across the North Slope, western Alaska, and the Aleutians. This is further supported by above normal sea surface temperatures (SSTs). A slight tilt toward dry conditions is indicated for southwestern Alaska and the Aleutians. The slight onshore flow in the Panhandle would promote above normal precipitation.
SSTs are elevated around the Hawaiian Islands. As such, the temperature outlook for Hawaii is dominated by above normal temperatures. The dynamical model guidance is also consistent on an increased wet signal for the islands.
Forecaster: Laura Ciasto
The next week 3-4 outlook will be issued on Friday, Nov 21, 2025
These outlooks are based on departures from the 1991-2020 base period
These are three category outlooks consistent with what is currently used for the monthly and seasonal forecasts.
The shading on the temperature map depicts the most favored category, either above-normal (A), below-normal (B), or near-normal (N) with the solid lines giving the probability ( >33%) of this more likely category (above, below, or near).
The shading on the precipitation map depicts the most favored category, either above-normal (A), below-normal (B), or near-normal with the solid lines giving the probability ( >33%) of this more likely category (above, below, or near).
In areas where the likelihoods of 2-week mean temperatures and accumulated precipitation amounts are similar to climatological probabilities, equal chances (EC) is indicated.