Our weather widget pulls your location based off of what your ISP returns for the city and state name. Sometimes this information is incorrect and in those cases we allow you to set a custom 5-digit ZIP code. Please enter your zip code below.

Significant Winter storm lurking for
late Nov? We say pump the brakes…
Get The Forecast!

Long Range Outlook

Important information:

  • Weather Weeklies video, found at http://epawaweather.com/weather-weeklies/ will continue every Sunday throughout the Winter season.
  • The EPAWA 2017-2018 Winter Outlook was released Wednesday November 8th exclusively in the premium forum. There will be no public release of the this outlook or any seasonal outlook product. To become part of the forum, visit http://epawaweather.com/winter-weather-alerts/ and select “Premium Weather Forum”.
  • Winter-only seasonal text alert options are now available at one low price for the entire 2017-2018 Winter season, visit http://epawaweather.com/winter-weather-alerts/ for sign-up options. There are also bundle options to add the forum at a discount at the bottom of the page.
DatesThreatsSignificanceConfidence
11/18-11/20TemperatureSlightly below averageVery high
11/21TemperatureSlightly above averageVery high
11/22-11/24TemperatureBelow averageVery high
11/25-11/26TemperatureSlightly below averageHigh
11/27-12/2TemperatureBelow averageModerately high
12/3-12/10TemperatureSlightly above averageModerately high
12/11-12/17TemperatureSlightly below averageModerate
11/18ShowersA warm front pushes through the region Saturday afternoon, then a cold front arrives during the overnight period, bringing showers with both mainly Saturday PM and overnight.Very high
11/25Cold frontA reinforcing cold front arrives next Saturday with a few showers possible along the boundary. The week leading up to this will be dry, including Thanksgiving/Black Friday.Moderate
November as a wholeTemperatureSlightly below average (-0.5°F to -1.5°F)High
November as a wholePrecipitationSlightly below average (-0.5" to -1.0")Moderately high
November as a wholeSnowfallSlightly below average - favors interior/mountainous regionsHigh
December as a wholeTemperatureSlightly below average (-0.5° to -1.5°)Moderately high
December as a wholePrecipitationSlightly above average (+0.5" to +1.5")Moderate
December as a wholeSnowfallAbove average, especially for areas NW of I-95Moderately high

Outlook table last updated: Friday November 17th, 12:00pm.  Next update: Friday November 24th.

This is a weekly updated public long range guidance product from EPAWA. For daily long range updates and more detailed updates M-F, please join the EPAWA forum. More information/sign-up at: http://epawaweather.com/my-pocket-meteorologist/ 

*Indications of above or below average temperatures in the table above are relative to what is considered “normal” using data collected over the long term for a particular date. This is collected and maintained by the National Climatic Data Center in conjunction with the National Weather Service actual data from previous years collected at official ASOS/climatology stations across our coverage area. Also note that as time moves forward into a different period as shown above, average temperatures for those dates will also change. See the example below using Philadelphia, PA as the climo station:

DateAverage Hi/LoEPAWA projection
November 18th55°F/39°FSlightly below average
November 25th52°F/36°FSlightly below average
December 2nd49°F/34°FBelow average
December 9th47°F/32°FNear to slightly above average

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.

Long range analysis: 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 rain or severe events, not publicly. To join this discussion and hear our updated thoughts from our team, visit The My Pocket Meteorologist Page by clicking HERE and select the “Premium Weather Forum” option.

Precipitation Discussion:

Precipitation:

The week will start off wet with a warm front bringing showers to the region on mainly Saturday afternoon, and then the cold front in association with the same parent low will sweep through the region on Saturday night. The southern half of the region will see generally under 1/2″ of total rainfall from this system, whereas the northern half due to being in closer proximity to the warm front will see between 1/2″ and 1″ of rainfall through late Saturday night/early Sunday AM. This system represents the only appreciable rainfall in the next week.

There will be the opportunity for a few lake effect snow showers for the far interior locations on Sunday, but largely no accumulations are expected except from a rogue heavier squall that has the ability to quickly whiten the ground in mainly higher elevations. There may be a brief shower for northern areas Tuesday night with a weak frontal boundary, but the next chance for any precipitation comes next Saturday, with a few showers possible ahead of the next reinforcing trough axis.

No large scale wintry systems are on the horizon for the next 7-10 days, and the next time frame to watch is after our projected mild period ends during the 2nd week of December.

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

November 18th-November 24th: Slightly below average

November 25th-December 1st: Slightly below average

December 2nd-December 8th: Near to slightly above average

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

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

 

Note:  Any image in the outlook is clickable for larger viewing

A warm front moves through the region Saturday afternoon, bringing scattered showers to mainly our central and northern sections.

ecm

As the parent system moves into Northern New England, the associated cold front moves through Saturday night with an additional round of showers for all areas.

ecm2

Pattern Discussion:

Pattern:

Much has been made of the cooler than average weather expected through much of the remainder of November, and this outlook is no different in keeping with those projections. But cold as a result of the -NAO blocking pattern does not necessarily translate to snow and snow potential as some have alluded to. It has nothing to do with the fact that it is November, since there have been memorable snowfalls near the Thanksgiving holiday as recent as 11/26/2014. What it does have to do with is a persistent zonal flow aloft and a fast-moving Pacific Jet. This jet has been lacking the amplification necessary to dig systems further south, and the fast-moving zonal flow has continued, and is expected to continue as a result.

Until we see changes in the Pacific that will enable the jet to become more amplified, cold and relatively dry pattern will continue, as systems quickly enter and exit uniformly, generally from west to east. Currently the Southern Oscillation Index (SOI) is, and has been consistently positive. This is a measure of the difference in pressure between Darwin, Australia and Tahiti. We need to see a shift to a negative SOI, which leads to more jet amplification downstream, and has a lag time of about 10-14 days to start affecting our sensible weather locally. This can be brought on with changes to the Madden-Julian Oscillation (MJO) from where it is now (circle of death, no help) to the Western Pacific, phases 6/7, which has been consistently projected by the ECMWF weeklies in December.

Until then, the cold resulting from the -NAO blocking pattern will dominate through the end of November, and then we expect a period of moderation during the 1st week of December, lasting into the beginning of week 2… and then another flip to colder than average anomalies, but this time with more moisture potentially coinciding with the cold. We have maintained confidence in a snowier than average month of December, and look for a storm with possible wintry implications during that 2nd week of December as we transition to a colder/stormier pattern.

November as a whole we project will finish slightly below average in most locales (-0.5°F to -1.5°F) when the dust settles November 30th, with high confidence. We started the month slightly above, but the remainder of the month from this point forward is expected to remain below average, and that averages the months as a whole to be slightly below by month’s end. The early December outlook suggests a slightly below average month as a whole as suggested by our leading analogs chosen for Winter 2017-2018, and observations are certainly pointing to that at this juncture.

Note:  Any image in the outlook is clickable for larger viewing

The GEFS shows trough over our region for the Thanksgiving holiday, which will result in below average temperatures, but also a dry period expected. This cold shot lasts through at least Black Friday.

gefs2

The Euro weeklies continue to suggest that after spending time in the circle of death, the best tropical forcing returns to the Western Pacific, which could result in a more favorable amplified jet for December.

mjo2

Next 3 weeks of US temperature departures

Images below are clickable for better viewing

Days 1-5 outlook – confidence VERY HIGH:

1-5

Days 6-10 outlook – confidence HIGH:

6-10

Days 11-15 outlook – confidence MODERATELY HIGH:

11-15

Days 16-20 outlook – confidence MODERATE:

16-20

Current U.S. Soil Moisture Anomaly

Below is a look at the latest snow cover propagation across Canada and the Contiguous United States.

This image will automatically update daily.

My Pocket Meteorologist

The My Pocket Meteorologist text alert program is gearing up for the upcoming Winter season. Seasonal options are now available. Click on the image below for more information.

mpm3

Forecaster: EPAWA Meteorologist Bobby Martrich
Discussion last updated:  Friday November 17th, 12:00pm