EPAWA's long range outlook is updated weekly every Friday morning before noon

Long range outlook last updated: Friday August 1st, 2025, 10:30 AM

Technical discussion is below for advanced readers:

Technical discussion below will feature two (2) subcategories: Precipitation, and Pattern Discussion. Storm possibilities will be discussed exclusively in the Premium Forum with intense model analysis leading up to any major snow, ice, or rain events, not publicly. To join this discussion and hear the updated thoughts from our team, visit The My Pocket Meteorologist Page by clicking HERE and select the "Premium Weather Forum" option.

Precipitation Discussion

OVERVIEW: The US drought monitor (photo toward the bottom of this outlook) maintains NO drought areas within our Pennsylvania, New Jersey, or Delaware locales. One abnormally dry area remains over Southern Baltimore County in Maryland, otherwise the remainder of Maryland has no drought designation. This is largely due to quite an impressive month of May with a top 5 rainfall month all-time in some locations, and generally near average precipitation following in June and July. Going forward, the month of August as a whole projections were maintained this week at a near average (-0.5" to +0.5") precipitation departure for the month as a whole. September monthly projections were introduced this week for a near to slightly below average (0.0" to -1.0") precipitation projection in accordance with longer term climate models and global observation trends.

Shorter term, a dry week is expected to begin August with high pressure dominating through at least midweek next week. As high pressure shifts offshore mid to late week next week, an area of low pressure may develop in response to a 500mb trough approaching from the west. This is currently modeled to graze the coastline in the Thursday night and Friday time frame, and could bring at least some shower activity to mainly our southeastern areas. Following this system we expect a warm front to approach either late Sunday or Sunday night with showers and perhaps thunderstorms. Given the lead time and timing uncertainty, the threat period was spread over two days - Sunday and/or Monday of the following week.

The month of August projections were maintained this week for a near average (-0.5" to +0.5") precipitation departure, with the expectation that we'll see a dry start and end to the month, with a slightly wetter than average middle two weeks of the month presently. The month of September projections for the month as a whole were introduced this week to a near to slightly below average (0.0" to -1.0") precipitation departure, using longer term climate models as well as seasonal trends.

Breakdown of precipitation departures from normal over the next several weeks:

August 2nd - August 8th: Below average

August 9th - August 15th: Near to slightly above average

August 16th - August 22nd: Near to slightly above average

August 23rd - August 29th: Near to slightly below average

August 30th - September 5th: Near average

September 6th - September 12th: Near to slightly below average

Public/free available maps will be updated when a threat is imminent for significant weather on the weather alerts page throughout the year:  http://epawaweather.com/weather-alerts/

Note:  Any image below is clickable for larger viewing  

Pattern Discussion

OVERVIEW:  The month of August projections for the month as a whole were maintained this week for a near to slightly above average (+0.0°F to +2.0°F) temperature projection, and the expectation of a cooler start to the month balanced by overall warmer than average conditions after the first 10 days of August. The month of September projections for the month as a whole were introduced this week for another near to slightly above average (+0.0°F to +2.0°F) temperature projection, using long term climate guidance and seasonal/global observation trends.

• The pattern change to cooler and more temperate conditions, to include lower humidity occurred on the final day of July as a cold front pushed through the region, and to begin August we'll see cooler temperatures and fair conditions as high pressure dominates. For the first 10 days or so of the month, the expectation is for generally near to slightly below average temperatures, then for those missing the typical summertime heat and humidity, both will make a return the following week. For the remainder of the month after the 11th-17th period, generally near to at times very slightly above average temperatures can be expected. Although the entirety of September is outside of our 5-6 week long range lead time purview, indications are that another month leaning to the slightly warmer side of average can be expected. 
  
  
• The Madden-Julian Oscillation (MJO) is currently in the Circle of Death (COD) or NULL phase, and is expected to flirt with a weak phase 1/2 signal during the first week of August before quickly collapsing in the COD. After the first week of the month, the remainder of the month is expected to remain in the COD. This typically promotes a more zonal flow with time, leading to more typical summerlike conditions returning that we expect beyond August 10th through the remainder of August.
  
  
• A composite average of the SST departures in the ENSO regions places it in ENSO neutral territory as it has been for the past several months. The Niño 1+2 region (eastern Pacific near Peru) is currently the warmest of the 4 ENSO regions at +0.1°C, whereas the other regions (Niño 3 and Niño 4) are near -0.1°C, and  Niño 3.4 is currently -0.2°C, placing the entire Pacific basin solidly in ENSO neutral territory. The expectation is for ENSO neutral to remain throughout the Summer months, which typically favors near to slightly above average temps in the June/July/August 3-month period, and near to slightly above average precipitation is typical of July and August. 

Average high temperatures are currently in the 84-87 °F range from north to south across our coverage region, which is about 1°F lower than at this point last week when we were in the midst of the highest climatological maximum temperatures of the entire year. Average temperatures will continue to very slowly abate over the coming weeks throughout August. Any above or below average stretches listed in the outlook will be relative to seasonal norms at that time, and it is important to note that cooler/warmer periods will be relative to the time of year we are talking about. For example, the slightly above average temperatures listed for the August 11th-17th period generally features highs in the upper 80s to near 90, coming at a time when average highs are typically in the middle 80s. Use the average highs/lows chart below providing a point of reference and transparency for what average temperatures are at each corresponding location through September 15th

The month of August projections were maintained this week for a near to slightly above average (+0.0°F to +2.0°F) temperature departure for the month as a whole, with the expectation of a cooler start to the month, followed by temperatures leaning to the warmer side of average past August 10th. The month of September as a whole was introduced this week for another near to slightly above average (+0.0°F to +2.0°F) temperature projection, using long term climate guidance and seasonal/global observation trends. 

Note:  Any image below is clickable for larger viewing

Long Range Outlook Table

Climatology

The departure from normal uses the average temperature for the date, averaging temps over 24 hours for any given location, using both high and low temperatures hourly during any particular day. This outlook determines warm vs. cool periods relative to normal temperatures.

Climate Prediction Center (CPC) Graphical Products

These products are from the NOAA Climate Prediction Center (CPC) and do not necessarily reflect the EPAWA forecast which is detailed above. All images below update automatically as the CPC releases new graphical products

U.S. Soil Moisture Anomaly

US drought monitor (NE US)