7:00 AM | Active pattern with a couple of systems over the next few days

6-Day Forecast

Today

Partly sunny, breezy and milder, highs in the low-to-mid 50’s

Tonight

Becoming cloudy, rain showers possible late, cold, lows in the upper 30’s

Saturday

Cloudy, chilly, periods of rain, upper 40's

Saturday Night

Mainly cloudy, cold, lingering rain possible early, upper 30’s

Sunday

Mainly cloudy, cold, chance for rain during the PM hours, mid-to-upper 40’s

Monday

Cloudy, chilly, periods of rain, mid-to-upper 40's

Tuesday

Cloudy, breezy, chilly, rain showers likely, upper 40’s

Wednesday

Partly sunny, windy, cold, mid 40’s

Discussion

The overall weather pattern looks be to on the cold side for much of the second half of March and it will also be quite active with numerous fast-moving systems. One such system will drop southeastward from the Upper Midwest into the Mid-Atlantic region by tomorrow bringing with it periods of rain. It’ll stay chilly on Sunday behind this system and then another wave of low pressure could slide just to our south on Monday bringing with it another round of rain. A strong cold front will then sweep through the region late Tuesday with more rain showers and it’ll usher in colder air for the middle and latter parts of next week.

Video

httpv://youtu.be/3LoACPTrMMo

11:45 AM | The cold will hold for the rest of March

Discussion

Spring will begin officially next week and there are already signs for very warm air to develop across the southwest US over the next few days with high temperatures flirting with the 90 degree mark in some desert locations. That warm air will, however, have a very difficult time of advancing anywhere near our part of the country over the next couple of weeks as an impressive “omega-shaped” blocking pattern will develop in the upper atmosphere to our north across Canada. This upper atmosphere blocking pattern will affect our temperature pattern in a couple of ways. First, it will act to force additional cold air masses into the central and eastern US from northern Canada and secondly, it will prevent any of the warm air building up in the southwest US from expanding into the northeastern US – at least not on any kind of consistent basis – through the rest of the month of March.

Two indices that can provide clues about the developing “omega-shaped” blocking pattern in the upper atmosphere include the Arctic Oscillation (AO) and North Atlantic Oscillation (NAO). These index values are related to the “oscillation” between the pressure differences in the North Atlantic and when they are in negative territory, blocking high pressure systems often develop around the Hudson Bay region of Canada. While this type of pattern allows for warming in that part of Canada, it also aids in pushing cold air masses into the northeastern part of the US. Both the European and GFS computer forecast models predict that the AO and NAO indices will remain in negative territory consistently through the remainder of March. In fact, the AO is about to tank from “slightly” to “sharply” negative values over the next week or so.

This overall colder-than-normal pattern will also be quite active and fast-moving over the next couple of weeks with a series of storms to potentially deal with, and snow cannot be ruled out for the Mid-Atlantic region given the expected cold weather. The first system will be a “clipper” that will quickly drop southeast from the Upper Midwest early this weekend and it’ll spread rain and/or snow showers into the I-95 corridor late Friday night and Saturday. A second system will then slide to our south early next week and it too can bring rain and/or snow showers to the Mid-Atlantic region.

Video

httpv://youtu.be/OGFyi2XKBO0

7:00 AM | Cold, windy for today and favorable conditions for comet viewing this evening

6-Day Forecast

Today

Partly sunny, windy, cold, highs in the low-to-mid 40’s

Tonight

Mostly clear, brisk, cold, lows near 30 degrees

Friday

Mostly sunny, breezy, not as cold, low 50's

Friday Night

Increasing clouds, chilly, rain and/or snow showers likely towards morning, mid 30’s

Saturday

Cloudy, chance for rain and/or snow showers, cool, low-to-mid 50’s

Sunday

Mostly cloudy, cold, chance for some rain, mid-to-upper 40’s

Monday

Cloudy, chilly, chance for more rain, mid-to-upper 40’s

Tuesday

Mostly cloudy, chilly, more showers possible, upper 40's

Discussion

High pressure will build into the region today following the passage of a secondary cold front late yesterday. Temperatures today will struggle to reach the mid 40's which is several degrees below normal for this time of year. Winds will be quite strong today out of the NW with gusts to 30 mph. Another cold front will approach the region on Saturday bringing with it the threat of rain and/or snow showers and yet another system is likely to slide just to our south early next week bringing with it the chance for more shower activity. One final note, skies should cooperate this evening for the viewing of Comet Pan-STAARS although it’ll be quite cold and breezy. Look for the comet in the western sky shortly after sunset.

Video

httpv://youtu.be/Zz5H0IfBnOI

7:00 AM | A secondary cold front moves through the region late today; colder air rushes in behind it for Thursday

6-Day Forecast

Today

Partly sunny, breezy and cooler, scattered rain showers possible during the afternoon hours, highs near 50 degrees

Tonight

Becoming partly cloudy, cold, lows near 30 degrees

Thursday

Mostly sunny, windy, cold, low-to-mid 40’s

Thursday Night

Mostly clear, brisk, cold, upper 20’s

Friday

Mostly sunny, still brisk and chilly, near 50

Saturday

Cloudy, chance for rain showers, chilly, low 50's

Sunday

Becoming cloudy, cold, chance for some rain late, upper 40’s

Monday

Mostly cloudy, cold, chance for some more rain, upper 40’s

Discussion

A strong cold front swept through the region yesterday causing some heavy rainfall and it will be followed closely by a secondary cold front that will cause afternoon clouds and possible showers. Cooler air has moved into the region behind the first front and even colder air will make Thursday likely the coldest day of the week. A clipper system will then drop out of the Upper Midwest towards the region on Saturday producing more rain showers in the area and yet another system will threaten us with more precipitation early next week. One final note, if skies cooperate this evening, look for Comet PAN-STAARS in the western sky near the crescent moon shortly after sunset; otherwise, wait until tomorrow evening as sky conditions should be quite favorable by then.

Video

httpv://youtu.be/dwPJhqlGm5I

1:10 PM | Comet PAN-STAARS is now viewable as soon as skies cooperate

Discussion

Despite today’s thick deck of clouds and rainfall that is associated with a strong cold front, there is a chance that skies will clear enough by early tonight in parts of the Mid-Atlantic region to allow for the viewing of Comet PAN-STAARS in the western sky shortly after sunset. If the comet is not viewable tonight then we’ll have to monitor the cloud cover situation for tomorrow night, but a secondary cold front will make that time somewhat questionable as well in the Mid-Atlantic region with late day clouds and possible showers. It would be nice if the skies would cooperate either tonight or tomorrow night since these two nights will present quite an opportunity for photographers given the fact that the comet will be right near the crescent moon in the western sky shortly after sunset. Thursday evening does promise to have favorable sky conditions although it’ll be quite cold and breezy, and the comet will have moved a bit farther away from the moon by then.

There have been reports that naked eye observation of the comet has been somewhat difficult in the twilight skies so binoculars or small telescopes would certainly be helpful with the viewing. Comet PAN-STAARS should only be visible with the naked eye for another couple of weeks, and perhaps into early April with binoculars and small telescopes. It certainly will be our last opportunity to view this comet as it has a very long elliptical orbit that takes more than 100 million years to complete.

7:00 AM | Today's cold frontal passage is quickly followed by a secondary front later tomorrow; colder weather returns for the second half of the week

6-Day Forecast

Today

Mostly cloudy, mild, occasional rain into the early afternoon hours and some of the rain will be heavy at times, highs near 60 degrees

Tonight

Becoming partly cloudy, turning colder late, mid-to-upper 30’s

Wednesday

Partly sunny, windy, colder, chance for a few afternoon rain showers, near 50

Wednesday Night

Becoming mostly clear, cold, near 30

Thursday

Coldest day of the week: Mostly sunny, breezy, cold, mid 40’s

Friday

Partly sunny, brisk, cold, upper 40’s

Saturday

Mostly cloudy, chilly, a few rain showers possible, low 50's

Sunday

Mostly sunny, chilly, near 50

Discussion

A strong cold front is sweeping towards the east coast and it’ll put an end to our warm spell as colder air will move in behind it for Wednesday and then a secondary front is expected to arrive late Wednesday with an even colder air mass behind it. High pressure will then takeover from Wednesday night into Saturday and temperatures will stay at below-normal levels through that period. Showers will continue today ahead of the first front and some of the rain will fall heavily at times with totals by late today of nearly an inch. The secondary front can bring a few rain showers to the region during the afternoon hours on Wednesday before gradual clearing sets in Wednesday night. Meanwhile, Comet PAN-STAARS is now visible to the naked eye in the northern hemisphere, but we’ll need to get some clearing conditions around here to view it in the western sky after sunset. Despite the clouds and rain today, there is a chance that enough clearing could occur by this evening to allow for viewing of the comet. Looking ahead beyond this week, a colder-than-normal pattern is quite likely for the much of the balance of March and the threat for snow may not be over yet.

Video

httpv://youtu.be/hJj8u4Ppy9Q

7:00 AM | Warm spell ends with Tuesday rain; colder air returns for the second half of the week

6-Day Forecast

Today

Mostly cloudy, mild, low 60’s (normal high is now 53 degrees)

Tonight

Mostly cloudy, mild, showers likely after midnight, lows in the lower 50's

Tuesday

Mostly cloudy, mild, occasional showers, upper 50’s

Tuesday Night

Becoming mostly clear, turning colder late, upper 30’s

Wednesday

Mostly sunny, breezy, chilly, near 50

Thursday

Mostly sunny, breezy, cold, mid-to-upper 40’s

Friday

Partly sunny, breezy, cold, upper 40’s

Saturday

Partly sunny, cold, mid 40’s

Discussion

High pressure will lose its control of our weather today as a strong cold front approaches from the west. Showers will begin later tonight and continue into the afternoon on Tuesday. Once the front clears the coast by Tuesday night, colder air will return for the middle and latter parts of the week with below normal temperatures returning to the region. One final note, Comet PAN-STAARS is now visible in the northern hemisphere and the sky conditions may get favorable by mid-week to view it in the western sky shortly after sunset.

Video

httpv://youtu.be/7Zfko7Ar7Xw

12:00 PM | Comet PAN-STAARS makes an appearance early next week

Discussion

There are not one, but two comets coming this year that could very well end up making 2013 remembered as the “Year of the Comet”. The first comet has actually been visible in the southern hemisphere during the past several weeks and it will become visible to the naked eye in the northern hemisphere early next week. The second comet called ISON comes late in the year (November/December) and that one promises to be one of the best of all-time according to some experts.

The first comet is officially known as Comet C/2011 L4 and it was discovered by the Panoramic Survey Telescope and Rapid Response System known as PAN-STARRS. As a result, the comet has taken on the name “Comet PAN-STARRS”. This will be the comet’s first visit as it has never been pulled in by the sun’s gravity so some surprises are possible. Comet PAN-STAARS made its closest approach to Earth on Tuesday (March 5th) when it passed by at a range of about 102 million miles. It’ll make its closest approach to the sun on Sunday, March 10th, at about 28 million miles from the sun – a bit closer than the planet Mercury. The comet will still be low in the western sky on Sunday and likely be lost in the sun’s glare even as the nucleus vaporizes and brightens. While the comet might be viewable by Monday evening, some experts have pinpointed to next Tuesday and Wednesday (3/12, 3/13) as two of the best dates for viewing the new comet in the northern hemisphere as it emerges in the western sunset sky. On those evenings, the thin crescent moon will be close to the comet in the western sky. PAN-STAARS will continue to be a bright object in the evening sky for the rest of March and during the first half of April.

In summary, to see the comet beginning early next week, look for it in the western sky shortly after sunset just to the left of the point on the horizon where the sun sets. It should be visible with the naked eye, but even better with binoculars or small telescopes. Let’s hope for clear skies and turn the clocks ahead this weekend.

7:00 AM | Milder air moves in for the weekend and early part of next week

6-Day Forecast

Today

Partly sunny, still breezy and cold, mid-to-upper 40’s

Tonight

Partly cloudy, cold, lows in the low 30’s

Saturday

Mostly sunny, milder, low 50’s

Saturday Night

Partly cloudy, cold, low 30’s

Sunday

Mostly sunny, even milder, mid 50’s

Monday

Partly sunny, still mild, upper 50’s

Tuesday

Mostly cloudy, mild, showers likely, low-to-mid 50’s

Wednesday

Partly sunny, colder, upper 40’s

Discussion

The coastal storm that has been stalled out over the Atlantic Ocean during the past 24 hours is still having an effect on parts of the Mid-Atlantic just to our north and east. Once the inverted trough associated with the coastal low finally pulls off to the northeast once and for all, the door will open up in the atmosphere for a substantial warm up during the weekend and early part of next week. In fact, temperatures are likely to soar well into the 50’s by Sunday and Monday and it’ll stay mild on Tuesday as well, but showers will be likely by then as a cold front approaches from the Midwest. Once that front passes by, colder air will return to the Mid-Atlantic region for the middle and latter parts of next week.

Video

httpv://youtu.be/hWXZXBq0RMI

7:00 AM | Still windy and chilly behind coastal storm; much milder for the weekend and early part of next week

6-Day Forecast

Today

Mostly sunny, bit still quite breezy and cold, highs in the low 40’s

Tonight

Partly cloudy, breezy, cold, lows in the upper 20’s

Friday

Partly sunny, still cold, low-to-mid 40’s

Friday Night

Partly cloudy, cold, upper 20’s

Saturday

Mostly sunny, milder, low 50's

Sunday

Partly sunny, still mild, mid 50’s

Monday

Partly sunny, mild, chance for a couple of showers, mid-to-upper 50’s

Tuesday

Mostly cloudy, mild, showers likely, mid 50’s

Discussion

The storm that produced a mixture of rain and snow yesterday in the immediate DC metro region and heavy snow across western Virginia is now spinning off the Northeast coast and it will actually swing an extended trough of low pressure down the Northeast coastline over the next 24 hours or so. The precipitation associated with this trough should stay to our north and east; however, and we'll just experience more wind and chill as a result of the lingering effects of this coastal storm. Once that system does exist the scene, it’ll open the door for some big changes temperature-wise for the weekend and also the early part of next week. "Spring-fever" alert for Sunday and Monday as temperatures should soar through the 50's, but a cold front on Tuesday will usher in colder air by the middle of next week.

Video

httpv://youtu.be/ZfRfjpe-XYY