southmdwatcher

Already seems like an overperformer, 0.39" so far, with much more incoming on radar. NWS Sterling updated forecast at 430am was for half to 3/4 inch of rain for my location.

1.59" today

Our region is upgraded to Slight Risk

PD1 was and is, to this day my all time favorite storm as well, living here in southern MD. Schools closed for a week, snow packed engine blocks, drifts up to the 2nd story and total whiteout conditions for hours.

SPC day 2 did upgrade to Slight risk for a very small corridor. HGR down to DCA east/northeastward to central NJ

DCA hit 99/72 at 135, 145 and 150pm

Yeah, those storms are falling apart pretty rapidly now.

The storms entering Pennsylvania above Pittsburgh, could interrupt the extreme heat this afternoon.

Wow, pretty darned good when you are fringed by the storms and still get 3.07" for the day and the vast majority was in 90 minutes. The Cameron Run roaring beside and under the Beltway was extremely impressive, I found out that it had dropped almost 2 feet from it's peak, when I passed through.

That blob of heavy rain following behind and moving south out of Howard and eastern Montgomery isn't going to help DC/Arlington/Alexandria and PG County at all.

https://forecast.weather.gov/wwamap/wwatxtget.php?cwa=lwx&wwa=flash flood watch Flood Watch National Weather Service Baltimore MD/Washington DC 1156 AM EDT Sun Jul 7 2019 DCZ001-MDZ003>006-011-013-014-016-503>506-VAZ031-050>057-501-502- 505-506-WVZ052-053-080000- /O.EXB.KLWX.FF.A.0008.190707T2200Z-190708T1000Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ District of Columbia-Washington-Frederick MD-Carroll- Northern Baltimore-Southern Baltimore-Prince Georges-Anne Arundel- Charles-Northwest Montgomery-Central and Southeast Montgomery- Northwest Howard-Central and Southeast Howard-Clarke-Orange- Culpeper-Prince William/Manassas/Manassas Park-Fairfax- Arlington/Falls Church/Alexandria-Stafford-Spotsylvania- King George-Northern Fauquier-Southern Fauquier-Western Loudoun- Eastern Loudoun-Berkeley-Jefferson- Including the cities of Washington, Hagerstown, Frederick, Ballenger Creek, Eldersburg, Westminster, Reisterstown, Cockeysville, Baltimore, Bowie, Suitland-Silver Hill, Clinton, College Park, Greenbelt, Laurel, Camp Springs, Glen Burnie, Annapolis, Severn, South Gate, Severna Park, Arnold, Odenton, St. Charles, Waldorf, Germantown, Damascus, Bethesda, Rockville, Gaithersburg, Silver Spring, Lisbon, Columbia, Ellicott City, Berryville, Orange, Gordonsville, Culpeper, Dale City, Manassas, Woodbridge, Lake Ridge, Montclair, Reston, Herndon, Annandale, Centreville, Chantilly, McLean, Franconia, Arlington, Alexandria, Falls Church, Falmouth, Fredericksburg, Dahlgren, Warrenton, Turnbull, Purcellville, Leesburg, Ashburn, Sterling, Martinsburg, Charles Town, and Shepherdstown 1156 AM EDT Sun Jul 7 2019 ...FLASH FLOOD WATCH IN EFFECT FROM 6 PM EDT THIS EVENING THROUGH LATE TONIGHT... The National Weather Service in Sterling Virginia has expanded the * Flash Flood Watch to include portions of Maryland, The District of Columbia, Virginia, and panhandle West Virginia, including the following areas, in Maryland, Anne Arundel, Carroll, Central and Southeast Howard, Central and Southeast Montgomery, Charles, Frederick MD, Northern Baltimore, Northwest Howard, Northwest Montgomery, Prince Georges, Southern Baltimore, and Washington. The District of Columbia. In Virginia, Arlington/Falls Church/Alexandria, Clarke, Culpeper, Eastern Loudoun, Fairfax, King George, Northern Fauquier, Orange, Prince William/Manassas/Manassas Park, Southern Fauquier, Spotsylvania, Stafford, and Western Loudoun. In panhandle West Virginia, Berkeley and Jefferson. * From 6 PM EDT this evening through late tonight * Slow moving showers and thunderstorms are expected tonight. Torrential rainfall may lead to totals exceeding 2 inches in a short period of time. This may cause flash flooding of small streams and other poor drainage urban areas.

Maybe the rain and associated coastal low will move through quicker than expected and allow for good rain tonight and earlier clearing tomorrow? Earlier timing is common with systems.

0.47" today, earlier we had some steady rain, now we have steady drizzle even without radar returns overhead.

We will not have the benefit of good shear for this event, but keep in mind that one of Virginia's best tornado events occurred in August 1993 and was not a tropical induced event.

We have had decent mid level lapse rates(around or just above 7 C/km) for the morning and early afternoon, not enough shear today.

https://www.spc.noaa.gov/products/watch/ww0315.html URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 315 NWS Storm Prediction Center Norman OK 1255 PM EDT Sun Jun 2 2019 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of District Of Columbia Western and Central Maryland Southeast Ohio Northern Virginia West Virginia Coastal Waters * Effective this Sunday afternoon and evening from 1255 PM until 800 PM EDT. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Scattered large hail and isolated very large hail events to 2 inches in diameter possible SUMMARY...Multiple rounds of thunderstorms are expected to develop this afternoon across the watch area, spreading eastward through the afternoon. The strongest cells in this region will pose a risk of damaging wind gusts and hail. The severe thunderstorm watch area is approximately along and 70 statute miles north and south of a line from 35 miles west northwest of Charleston WV to 30 miles north northeast of Patuxent River MD.

Spotter reported tornado over/near Massaponax as per latest warning update

Today seems to be a discrete storm mode, question for us will be if that can occur tomorrow and hold on for an evening Bay breeze or low level jet?

North of Baltimore, and northeastward through Philadelphia to central NJ could have quite a rough evening. Storm mode looks to stay discrete as storms continue to move east southeast towards the areas of best parameters as the day/evening progresses. Tomorrow could be quite a rough day in our area.

6z 3kNAM shows scattered severe storms rolling through our region between 18z and 21z. 9z HRRR run shows similar scenario with more storms. 10z HRRR run was much more quiet. The MCS is in western Ohio and southern Indiana, We should see some decent storms later today.

I am in Alexandria and the sun is trying to break through here right now as well.

74 degrees and breaks of good sun coming north.from Charles County

6Z 3km NAM shows the strongest 850mb winds are running through VA later this afternoon. CAPE of 1000-1500 runs Fredericksburg and then southward.

We shall see what SPC and Sterling have to say over the next few hours. The lapse rates over us now are quite strong. That will move out as we head towards morning. The sun will definitely be out for some period of time tomorrow, just a matter of how long and whether a new batch of prefrontal storms breaks out and squashes any substantial buildup of instability. The timing of the event across AL/MS is slightly quicker than was expected. That throws wrinkles into our forecast tomorrow.

That was from 15Z run of SREF, this is 21Z