arlwx

Looks like it's still damp here in Arlington. ((Although earlier they did salt the Hill of Doom here.))

LWX on the start of next week: High pressure will dominate Saturday with a little moderation in temps. However, by Sunday, another system is pushing northeastward towards us, with warm advection precip breaking out in our region by day`s end. Cold air looks marginal by this point, so while a mix may start, this again looks like a system which will transition to more liquid than frozen. The low track towards the lower Great Lakes certainly will not help keep the cold air around, though some damming could result in more wintry mix in the favored spots northwest of I-95.

As a back-surgeried warminista, I won't breathe a sigh of relief until Febrrary is ended.

A few stray flakes in Arlington.

Waiting until February, according to the GFS, to start looking for my flamethrower.

Arlington just sent down a truck to spray sand and salt all over The Hill of Doom. They must be concerned about the freeze forecast for tonight. They normally don't do it for the coating that was on the road.

Rain mixing in near DCA.

I guess LWX wanted to note the prospect of freezing rain... URGENT - WINTER WEATHER MESSAGE National Weather Service Baltimore MD/Washington DC 400 PM EST Tue Dec 15 2020 DCZ001-VAZ054-160500- /O.NEW.KLWX.WW.Y.0014.201216T1500Z-201217T0600Z/ District of Columbia-Arlington/Falls Church/Alexandria- 400 PM EST Tue Dec 15 2020 ...WINTER WEATHER ADVISORY IN EFFECT FROM 10 AM WEDNESDAY TO 1 AM EST THURSDAY... * WHAT...Mixed precipitation expected. Total snow and sleet accumulations of 1 to 2 inches. A light glaze of ice is also possible on elevated surfaces. * WHERE...In District of Columbia, District of Columbia. In Virginia, Arlington/Falls Church/Alexandria. * WHEN...From 10 AM Wednesday to 1 AM EST Thursday. Snow will overspread the area between 9 and 11 AM, and change to sleet and rain during the early afternoon. Some rain may freeze on elevated surfaces. * IMPACTS...Plan on slippery road conditions. The hazardous conditions could impact the evening commute.

As a warminista near DCA, fit me into the "just where I want it" bingo square.

Cross-posting: URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 515 NWS Storm Prediction Center Norman OK 105 PM EST Mon Nov 30 2020 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Delaware Eastern Maryland Central and Southern New Jersey Southeast Pennsylvania Eastern Virginia Coastal Waters * Effective this Monday afternoon and evening from 105 PM until 700 PM EST. * Primary threats include... A couple tornadoes possible Scattered damaging wind gusts to 70 mph possible

URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 515 NWS Storm Prediction Center Norman OK 105 PM EST Mon Nov 30 2020 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Delaware Eastern Maryland Central and Southern New Jersey Southeast Pennsylvania Eastern Virginia Coastal Waters * Effective this Monday afternoon and evening from 105 PM until 700 PM EST. * Primary threats include... A couple tornadoes possible Scattered damaging wind gusts to 70 mph possible

Tornado watch issued. For central/southern MD. MD/DE Eastern Shore And parts of NJ.

BWI: 17 DCA: 14 IAD: 20 RIC: 10 SBY: 7 ((This warminista is hoping for a repeat of last year, but going more with climo.))

LWX forecasts show potential freezes for Wednesday and Thursday mornings for BWI, maybe RIC too.

DCA is reporting 2.17" so far for the event. The Four Mile Run gauge shows about 2.3".

The GFS currently shows no love for freezinists through 19 Nov. ((so although I didn't spot the contest sooner, I would be on course to be busting bigtime on BWI (31 Oct), RIC (8 Nov) and some for DCA too (15 Nov).))

Close at IAD and BWI but still no cigar. ((oops, just spotted IAD snuck in a 32 on 31 Oct)) DCA 42 BWI 35 IAD 33 RIC 38

URGENT - WEATHER MESSAGE National Weather Service Baltimore MD/Washington DC 414 PM EDT Thu Oct 29 2020 MDZ004>006-505-507-508-VAZ505-WVZ053-300415- /O.UPG.KLWX.FZ.A.0010.201031T0700Z-201031T1300Z/ /O.NEW.KLWX.FZ.W.0013.201031T0700Z-201031T1300Z/ Frederick MD-Carroll-Northern Baltimore-Northwest Howard- Northwest Harford-Southeast Harford-Western Loudoun-Jefferson- Including the cities of Frederick, Ballenger Creek, Eldersburg, Westminster, Reisterstown, Cockeysville, Lisbon, Jarrettsville, Aberdeen, Purcellville, Charles Town, and Shepherdstown 414 PM EDT Thu Oct 29 2020 ...FREEZE WARNING IN EFFECT FROM 3 AM TO 9 AM EDT SATURDAY... * WHAT...Sub-freezing temperatures as low as 31 expected. * WHERE...In Maryland, Frederick MD, Carroll, Northern Baltimore, Northwest Howard, Northwest Harford and Southeast Harford Counties. In Virginia, Western Loudoun County. In West Virginia, Jefferson County. * WHEN...From 3 AM to 9 AM EDT Saturday. (snip)

Severe Thunderstorm Watch SEVERE THUNDERSTORM WATCH OUTLINE UPDATE FOR WS 250 NWS STORM PREDICTION CENTER NORMAN OK 230 PM EDT THU JUN 4 2020 SEVERE THUNDERSTORM WATCH 250 IS IN EFFECT UNTIL 1000 PM EDT FOR THE FOLLOWING LOCATIONS VAC013-015-043-047-059-061-069-079-091-107-113-137-139-153-157- 165-171-187-510-600-610-660-683-685-790-820-840-050200- /O.NEW.KWNS.SV.A.0250.200604T1830Z-200605T0200Z/ VA . VIRGINIA COUNTIES INCLUDED ARE ARLINGTON AUGUSTA CLARKE CULPEPER FAIRFAX FAUQUIER FREDERICK GREENE HIGHLAND LOUDOUN MADISON ORANGE PAGE PRINCE WILLIAM RAPPAHANNOCK ROCKINGHAM SHENANDOAH WARREN VIRGINIA INDEPENDENT CITIES INCLUDED ARE ALEXANDRIA FAIRFAX FALLS CHURCH HARRISONBURG MANASSAS MANASSAS PARK STAUNTON WAYNESBORO WINCHESTER $$ SEVERE THUNDERSTORM WATCH OUTLINE UPDATE FOR WS 250 NWS STORM PREDICTION CENTER NORMAN OK 230 PM EDT THU JUN 4 2020 SEVERE THUNDERSTORM WATCH 250 IS IN EFFECT UNTIL 1000 PM EDT FOR THE FOLLOWING LOCATIONS MDC001-003-005-013-021-025-027-031-033-043-510-050200- /O.NEW.KWNS.SV.A.0250.200604T1830Z-200605T0200Z/ MD . MARYLAND COUNTIES INCLUDED ARE ALLEGANY ANNE ARUNDEL BALTIMORE CARROLL FREDERICK HARFORD HOWARD MONTGOMERY PRINCE GEORGES WASHINGTON MARYLAND INDEPENDENT CITIES INCLUDED ARE BALTIMORE CITY $$

Severe Thunderstorm Watch issued for DC and surrounding counties.

If LWX is to be believed, I'd expect quite a few road closures due to small streams out of their banks. I DO hope Arlington has fixed its drains and alerted persons living/working in the usual suspect spots (think Westover, the area of South Glebe Road near the sewage plant, etc.).

From the latest LWX discussion: (snip) .SHORT TERM /THIS EVENING THROUGH FRIDAY NIGHT/... Notable trends seen this cycle among global models were that the GFS trended deeper/more amplified, closer to the Euro with the upper level trof/closed low fcst to dig across the mid-Atlc states Thu-Fri. Timing differences with respect to upper level trof axis moving across the area have decreased significantly and the rainfall potential has increased somewhat since 24 hrs ago. Anticipating a widespread moderate to heavy rainfall event late Wed night into early Thu evening with widespread 1.5 -2.5 inches with the potential for up to 4 inches (reasonable worst case scenario) with heaviest amounts east of the Blue Ridge and Catoctin mountains. Forcing and moisture will be plentiful with instability lacking which would limit rainfall rates, but prolonged period of the event, deep moisture, and strong upper level divergence will compensate for lack of instability. While heaviest amounts are expected east of the Blue Ridge, enough spread is shown in the ensembles and difference percentiles to include areas west of the Blue Ridge. Have issued a Flood Watch for much of the area separated with two segments, a western segment with beginning and ending time of 08Z-16Z Thu, and an eastern segment running from 16Z Thu-02Z Fri. (snip)

LWX is suggesting some may need a run to the battery store... (snip) The dry slot will work its way into the area later Monday morning and the cold front will pass through the area Monday afternoon into Monday evening. On the edge of the dry slot and ahead of the cold front is where stronger thunderstorms are most likely Monday morning and afternoon. Long and curved hodographs are seen in forecast soundings to the very strong winds aloft. The very strong wind flow, along with strong warm and moist advection, combined with forcing from the front and somewhat of an enhancement in instability on the edge of the dry slot, suggests that a broken line of showers and thunderstorms will develop Monday morning and progress east and northeast into Monday afternoon. Embedded supercells are possible withing the line along with a possible QLCS feature. Therefore, damaging winds are a concern with convection Monday along with an increased threat for a tornado and large hail. Localized flash flooding cannot be ruled out, but the storms should have enough motion to keep that threat localized. Another threat for overnight and Monday will be gradient wind outside of heavier showers and thunderstorms. For the overnight, a very strong low-level jet will develop but with warm advection and showers overhead it will be tough to mix down. It will still turn out quite breezy with frequent gusts around 20-35 mph for most areas. There could be gusts 40-55 knots along the highest ridge tops above 3000 feet, but did not include these in a wind headline at this time since it will be very isolated. However, with strong warm advection Monday morning, the mixing layer will begin to increase, causing winds to increase. For Monday afternoon, there will be dry advection and weak cold advection behind the dry slot. This will enhance the mixing layer even more. As of now, it appears that wind gusts will be around 45-55 mph for most areas late Monday morning through most of Monday afternoon. A Wind Advisory will likely be needed. Did issue a High Wind Watch for the ridges of the Allegheny and Potomac Highlands as well as the Blue Ridge Mountains where stronger winds are likely over the higher elevations. Also included central Mineral, Grant, and Allegany Counties due to a downsloping flow off the mountains that may enhance winds in those areas. Gusts around 60 mph are possible. One thing to note is that there may be numerous fallen trees if these strong winds do occur, and that is because the ground will be much more saturated due to recent rainfall, compared to when the ground is mainly dry during these types of gradient wind events. (snip)

The latest from LWX: NEAR TERM /THROUGH TONIGHT/... Satellite and observational trends show that dense fog is expanding in areal coverage as high clouds shift to the east. NSSL-WRF ARW synthetic imagery shows low clouds persisting all day east of the Blue Ridge, the eastern panhandle of WV, and northern MD. Based on its output, areas south of Winchester to Staunton are the only ones that are expected to experience clear skies. It will likely remain quiet through about 21Z, then widespread showers and possible thunderstorms are expected as low pressure forms along the Appalachians and Blue Ridge and develops north northeastward. The most recent model guidance showed a trend toward less instability/CAPE available due low overcast expected to persist all day. Other parameters such as model flash rate and lifted indices also showed a downward trend in t-storm potential. The areas of greater risk for any severe wx seems to be east of the Appalachians to the I-81 corridor where the most sunshine is expected and generally west of where SPC placed the marginal risk. Cdfnt will sweep through the area between 03Z-06Z Thu with showers ending quickly with fropa. Colder air will follow in its wake with showers turning quickly into snow showers over the Appalachians where sub-advisory snow accumulations are expected. A strong pressure surge behind the front will cause strong winds at higher elevations and have issued a Wind Advisory for the highest elevs from midnight tonight to 15Z Thu.

Late morning update from LWX: .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... Wednesday will start cloudy with areas of drizzle and fog. Ceilings should gradually lift through the day. A second area of low pressure will form along the Blue Ridge and develop northeastward as it reaches southern New England by 12Z Thursday. A deepening upper trough taking a negative tilt will provide large scale forcing for upward vertical motion with widespread showers and scattered thunderstorms expected Wed afternoon through late evening. Given strengthening wind fields aloft and increasing shear values, isolated severe thunderstorms are possible late Wed into early evening before line of showers and embedded t-storms reaches the Chesapeake Bay by 03Z Thu. Cold air will filter in quickly on NW flow with snow showers likely accumulating 1-3 inches over western Grant and Pendleton Counties. Blustery on Thu with winds gusting up to 40 mph.