ROCKVILLE SNOW UPDATE/FORECAST #RKV #WEATHER

A few days before springing forward to Daylight Savings Time, winter is going out kicking and screaming with another snowstorm headed our way tonight. We will be experiencing rain throughout the day today with our relatively warmer temperatures (our high will be 46°F this afternoon), but overnight that will switch to snow. By 5 AM Thursday, we'll be at the freezing mark - just in time for rush hour, of course.

Snow will begin to taper off by 5 PM Thursday, and our total accumulation will be in the 3"-7" range, with some forecasters calling for 10" at the higher end of the spectrum. A frigid Friday means we'll be iced in by whatever has fallen until it begins to melt Saturday. If recent storms are a guide, that initial freeze will slow the melting process even once temperatures have gone above freezing this weekend.

Our current temperature is a downright-balmy 39°, and fog will be a problem early this morning. Take an umbrella. Winds are WSW at 4 MPH.

Stay tuned here and on Twitter at @RockvilleNights for updates throughout the storm tonight and tomorrow.

ROCKVILLE SNOW UPDATE AND FORECAST #RKV

The DC area will be under a Winter Weather Advisory from noon until 10:00 PM tonight, as snow, sleet and freezing rain associated with Winter Storm Thor are expected to create hazardous road conditions this evening.

Thor is expected to hit at midday. We will be getting up to an inch of snow and sleet, according to the NWS; the Weather Channel is showing slightly higher amounts.

What could be worse for drivers, falling limbs and trees, and power outages, is that we are again facing a coating of ice around a tenth of an inch today.

It is currently a frigid 22°F. The good news is that, beginning around 7:00 PM tonight, we will be rising above freezing, and continue to heat up overnight. That will turn the precipitation into rain.

Prepare to enjoy a rainy but comparatively toasty 47° high on Wednesday.

ROCKVILLE SNOW UPDATE - HOW MANY INCHES OF SNOW IN ROCKVILLE?

A winter storm warning is in effect across the region today from 2:00 PM until 2:00 PM Monday. Rain is forecast to begin this afternoon, and change over to snow as the sun sets. The heaviest snow will fall during the overnight hours tonight. Currently, the National Weather Service is calling for accumulation of 5 inches, or more. Temperatures will be in the 20s overnight.

Winds during the storm will gust up to 20 MPH, but average around 10.

Highs on Monday will remain in the lower 30s, meaning travel will be dangerous, and road conditions could remain hazardous throughout the day.

Stay tuned for updates on this very late winter storm.

ROCKVILLE DECLARES SNOW EMERGENCY + HOW MANY INCHES OF SNOW TO EXPECT

The City of Rockville has declared a snow emergency, as a major winter storm approaches the city. A snow emergency means residents should remove vehicles from streets by 6 PM tonight. If there is not adequate space to do so, residents are asked to park on the even-numbered side of the street. These non-mandatory requests are meant to make it easier for snowplow drivers to navigate streets, and speed up the snow removal process.

What is mandatory, is the city's snow-shoveling law:

Snow must be removed from sidewalks, steps, driveways, parking spaces and similar paved areas for public use (including access ramps and curbs) within 48 hours after a snowfall of three to 10 inches and within 72 hours after a snowfall of more than 10 inches. When clearing paved areas, provide a safe, unobstructed, passable path 36 inches wide.

Residents are asked to avoid driving during the storm, if possible. If you have a non-emergency weather-related issue to report to city police, call 240-314-8900. For emergencies, obviously, call 911.

Maryland Gov. Martin O'Malley has declared a snow emergency for the state, as well.

ROCKVILLE FORECAST

Heavy snow is expected to begin falling during the evening rush hour tonight. Current projections are for 3-6" tonight, and 4-8" Thursday, for a total of up to 10". The high today will be 30-32 F, and the high Thursday will be 34 F.

ROCKVILLE SNOW FORECAST - WEATHER

The snow forecast for Rockville is insignificant today. Expect a mix of rain and snow between early morning and mid-afternoon. Temperatures are forecast to remain above freezing throughout the day. Clouds will give way to clear skies by 8:00 tonight, but temperatures will drop below freezing - expect them to be in the upper twenties overnight.

ROCKVILLE SNOW UPDATE - WINTER STORM SATURN

Well, so far the weather experts have been dead wrong on Winter Storm Saturn. Rain starting at 5 PM yesterday? Never happened. 1-3" of snow last night? Nope. Now they're telling us the worst is still to come today. I don't have much faith in these "experts."

Roads are slick but quite passable at this hour.

Schools and the federal government are closed. The Maryland state government is on liberal leave.

Almost all Metrobus routes are running, but some are on "limited" schedules. That means more waiting than usual at bus stops.

Forecast remains the same, with snow accumulation of 5-6" by tomorrow, while other models say anywhere from 3-12".

Stay tuned here and at @RockvilleNights on Twitter for updates.

HOW MANY INCHES OF SNOW WILL ROCKVILLE GET FROM WINTER STORM SATURN?

Rockville is under a Winter Storm Watch right now. The sun is shining, but there's a wintry chill in the air.

Winter Storm Saturn is on its way to the DC area.

How many inches of snow will end up falling on Rockville tonight and on Wednesday?

The average prediction is 5-6 inches. Some forecasters say it could be as many as 8-12.

But here's an intriguing prediction: the now-famous Euro Model is saying the DC area will receive a 1-3" accumulation. This contradicts the majority of forecasts. Yet it is intriguing because the Euro Model was dead-right about the hurricane last fall.

The fact is, nobody knows. But conditions are right for up to a foot of snow.  And it is supposed to be a wet, heavy snow. That means more effort to shovel and plow for humans and machines.

Even though the Euro Model sounds unlikely, you can't rule out the data from a model that has been accurate so many times.

The fact that temperatures will rise above freezing on Wednesday could certainly reduce the potential total accumulation.

But that ice and slush will freeze solid after dark again, so watch out.

Today, expect light showers by 5:00 PM, changing over to snow after dark.  Accumulation of 1-2" possible tonight. Winds gusting to 30 MPH.

Wednesday, heavy showers and heavy snow. Accumulation of 5-12" possible through Thursday morning. Winds will gust to 35 MPH. Visibility could be affected if snowfall is heavy, due to winds.

Metro and Metrobus are total wildcards in recent years, in contrast to their past practice of operation during all but the worst snows in prior decades.

Stay tuned here and at @RockvilleNights on Twitter for updates throughout the storm!