May Discobs 2022

[CAPE]

Just now, Chris78 said:

Looks like the euro in regards to precip distribution 

The Euro has been consistently slower with the exit of the secondary coastal low than other guidance, thus prolonging the rain, esp for areas to the south and east. That's why it has a more even distribution of heavy rainfall through the region.

[high risk]

1 hour ago, WxUSAF said:

CMC went to keeping rain through Sunday which sucks.

      Two days of wet and upper 40s during a May weekend is as ugly as it gets.

[CAPE]

Latest AFD from Mount Holly-

A strong, slow moving coastal storm will affect the region for most of the weekend. Widespread rain will be ongoing early Friday night as a warm front sits south of our region. Primary low pressure over the Ohio Valley will weaken Friday night as a secondary low develops just off the Delmarva coast in response to an approaching upper level trough and strong low level frontogenetic forcing. That secondary low will continue to develop off the coast and sit with little movement Saturday into Sunday, before strong high pressure to the north begins slowly forcing it south. The low will also start to become vertically stacked during this time as the upper level trough closes off and moves over the surface low. This will cause the surface low to start slowly weakening, but thanks to strong high pressure to the north, the pressure gradient will remain very strong, reinforcing the onshore flow.

This is quite an anomalous system for the season, a true Nor`easter with multiple days of rain and battering wind likely especially at the coast. The steadiest rain is expected from Friday night through Saturday, but periods of rain and showers are likely to continue into Sunday. We`ll first deal with the initial thump of overrunning precipitation, which will be what starts during the daytime on Friday. As the coastal low spins up, we`ll then see areas of banded frontogenetic precipitation on its northwest flank which will continue to bring areas of rain through Sunday. With time on Sunday, as the low slowly shifts further south, northern portions of the area may dry out, while showers likely continue to the south and east.

Temperatures will also be a story this weekend. The combination of rain, a thick cloud deck, and strong onshore winds will lead to much below normal temperatures both Saturday and Sunday. Highs mostly in the low to mid 50s are expected, and a lot of time will be spent in the 40s. Combined with the wind and rain, the weekend looks downright ugly overall.

[SnowenOutThere]

2 hours ago, CAPE said:

Latest AFD from Mount Holly-

A strong, slow moving coastal storm will affect the region for most of the weekend. Widespread rain will be ongoing early Friday night as a warm front sits south of our region. Primary low pressure over the Ohio Valley will weaken Friday night as a secondary low develops just off the Delmarva coast in response to an approaching upper level trough and strong low level frontogenetic forcing. That secondary low will continue to develop off the coast and sit with little movement Saturday into Sunday, before strong high pressure to the north begins slowly forcing it south. The low will also start to become vertically stacked during this time as the upper level trough closes off and moves over the surface low. This will cause the surface low to start slowly weakening, but thanks to strong high pressure to the north, the pressure gradient will remain very strong, reinforcing the onshore flow.

This is quite an anomalous system for the season, a true Nor`easter with multiple days of rain and battering wind likely especially at the coast. The steadiest rain is expected from Friday night through Saturday, but periods of rain and showers are likely to continue into Sunday. We`ll first deal with the initial thump of overrunning precipitation, which will be what starts during the daytime on Friday. As the coastal low spins up, we`ll then see areas of banded frontogenetic precipitation on its northwest flank which will continue to bring areas of rain through Sunday. With time on Sunday, as the low slowly shifts further south, northern portions of the area may dry out, while showers likely continue to the south and east.

Temperatures will also be a story this weekend. The combination of rain, a thick cloud deck, and strong onshore winds will lead to much below normal temperatures both Saturday and Sunday. Highs mostly in the low to mid 50s are expected, and a lot of time will be spent in the 40s. Combined with the wind and rain, the weekend looks downright ugly overall.

For anyone reading it I recommend replacing the word rain with snow. 

[BlizzardNole]

3 hours ago, CAPE said:

Latest AFD from Mount Holly-

A strong, slow moving coastal storm will affect the region for most of the weekend. Widespread rain will be ongoing early Friday night as a warm front sits south of our region. Primary low pressure over the Ohio Valley will weaken Friday night as a secondary low develops just off the Delmarva coast in response to an approaching upper level trough and strong low level frontogenetic forcing. That secondary low will continue to develop off the coast and sit with little movement Saturday into Sunday, before strong high pressure to the north begins slowly forcing it south. The low will also start to become vertically stacked during this time as the upper level trough closes off and moves over the surface low. This will cause the surface low to start slowly weakening, but thanks to strong high pressure to the north, the pressure gradient will remain very strong, reinforcing the onshore flow.

This is quite an anomalous system for the season, a true Nor`easter with multiple days of rain and battering wind likely especially at the coast. The steadiest rain is expected from Friday night through Saturday, but periods of rain and showers are likely to continue into Sunday. We`ll first deal with the initial thump of overrunning precipitation, which will be what starts during the daytime on Friday. As the coastal low spins up, we`ll then see areas of banded frontogenetic precipitation on its northwest flank which will continue to bring areas of rain through Sunday. With time on Sunday, as the low slowly shifts further south, northern portions of the area may dry out, while showers likely continue to the south and east.

Temperatures will also be a story this weekend. The combination of rain, a thick cloud deck, and strong onshore winds will lead to much below normal temperatures both Saturday and Sunday. Highs mostly in the low to mid 50s are expected, and a lot of time will be spent in the 40s. Combined with the wind and rain, the weekend looks downright ugly overall.

Some bits out of that disco with the obligatory why not February 

• A strong, slow moving coastal storm
• That secondary low will continue to develop off the coast and sit with little movement Saturday into Sunday
• initial thump of overrunning precipitation
• As the coastal low spins up...frontogenetic precipitation on its northwest flank

 

[WEATHER53]

Snower November  to March but just not May 

[Weather Will]

2022

...FLOOD WATCH IN EFFECT FROM NOON EDT TODAY THROUGH LATE TONIGHT...

* WHAT...Flooding caused by excessive rainfall is possible.

* WHERE...Portions of Maryland, northwest Virginia and West
  Virginia, including the following areas: in Maryland, Carroll,
  Central and Eastern Allegany, Extreme Western Allegany, Frederick
  MD, Garrett and Washington. In northwest Virginia, Clarke,
  Frederick VA, Shenandoah and Warren. In West Virginia, Berkeley,
  Eastern Grant, Eastern Mineral, Eastern Pendleton, Hampshire,
  Hardy, Jefferson, Morgan, Western Grant, Western Mineral and
  Western Pendleton.

* WHEN...From Noon EDT today through late tonight.

* IMPACTS...Excessive runoff may result in flooding of rivers,
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - Widespread rainfall totals of 1-3 inches are expected through
    tonight, with localized totals up to 4 inches. This may lead
    to localized instances of flooding.
  - http://www.weather.gov/safety/flood

[yoda]

yay

Flood Watch
National Weather Service Baltimore MD/Washington DC
313 AM EDT Fri May 6 2022

DCZ001-MDZ011-013-014-503>506-VAZ052>054-501-505-506-061515-
/O.NEW.KLWX.FA.A.0003.220506T2100Z-220507T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
District of Columbia-Southern Baltimore-Prince Georges-Anne Arundel-
Northwest Montgomery-Central and Southeast Montgomery-Northwest
Howard-Central and Southeast Howard-Prince William/Manassas/Manassas
Park-Fairfax-Arlington/Falls Church/Alexandria-Northern Fauquier-
Western Loudoun-Eastern Loudoun-
Including the cities of Silver Spring, South Gate, Bowie, Arlington,
Annapolis, Manassas, Odenton, Damascus, Falls Church, Purcellville,
Bethesda, Chantilly, Centreville, Sterling, College Park, Columbia,
Herndon, Severna Park, Greenbelt, Germantown, Leesburg, McLean, Camp
Springs, Rockville, Arnold, Dale City, Suitland-Silver Hill, Lake
Ridge, Laurel, Severn, Reston, Montclair, Baltimore, Alexandria,
Clinton, Glen Burnie, Ashburn, Ellicott City, Woodbridge,
Washington, Annandale, Warrenton, Lisbon, Gaithersburg, and Franconia
313 AM EDT Fri May 6 2022

...FLOOD WATCH IN EFFECT FROM THIS AFTERNOON THROUGH LATE TONIGHT...

* WHAT...Flooding caused by excessive rainfall is possible.

* WHERE...DC and portions of Maryland and northern Virginia,
  including the following areas: the District of Columbia. In
  Maryland, Anne Arundel, Central and Southeast Howard, Central and
  Southeast Montgomery, Northwest Howard, Northwest Montgomery,
  Prince Georges and Southern Baltimore. In northern Virginia,
  Arlington/Falls Church/Alexandria, Eastern Loudoun, Fairfax,
  Northern Fauquier, Prince William/Manassas/Manassas Park and
  Western Loudoun.

* WHEN...From this afternoon through late tonight.

* IMPACTS...Excessive runoff may result in flooding of rivers,
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - Widespread rainfall totals of 1-3 inches are expected through
    tonight. This may lead to localized instances of flooding.
  - http://www.weather.gov/safety/flood

[mappy]

15 hours ago, WxUSAF said:

We have orioles tickets. 

Ugh. I hope it stays dry enough for you! 

[dailylurker]

Looking forward to seeing what flooding is like here on Parrs Ridge this summer. Lots of crazy hills, valleys and ridges. Water must go crazy around here when we flood. My neighbor said they get springs basically shooting out of ground when it gets bad. Anyway.. looking forward to a nice rainy couple days. It's good for the vegetation.

[yoda]

 

[Eskimo Joe]

1 hour ago, dailylurker said:

Looking forward to seeing what flooding is like here on Parrs Ridge this summer. Lots of crazy hills, valleys and ridges. Water must go crazy around here when we flood. My neighbor said they get springs basically shooting out of ground when it gets bad. Anyway.. looking forward to a nice rainy couple days. It's good for the vegetation.

Woodbine doesn't flood too much. Sams Creek Rd @ Oak Orchard Rd towards New Windsor is more of an issue. Skyesville has issues in the historic district.

[Herb@MAWS]

I'll just hope I can mow the lawn by Mon/Tues.  Needs it now.

At 8am, 56 in Columbia.

[Eskimo Joe]

HRRR throws a decent number of discrete cells and even a few UHI tracks near RIC this afternoon. Couple of beefy looking line segments event up through the NW suburbs of DC.

[yoda]

6 minutes ago, Eskimo Joe said:

HRRR throws a decent number of discrete cells and even a few UHI tracks near RIC this afternoon. Couple of beefy looking line segments event up through the NW suburbs of DC.

I know the best chances of severe are down south of us... but i wouldn't mind some good storms this afternoon/evening

[WxUSAF]

27 minutes ago, yoda said:

I know the best chances of severe are down south of us... but i wouldn't mind some good storms this afternoon/evening

I would. My plane lands at 9pm.

[Eskimo Joe]

9 minutes ago, WxUSAF said:

I would. My plane lands at 9pm.

[weatherCCB]

Moderate downpour moving thru

0.25”   57/55

[yoda]

@Eskimo Joe maybe this is what the HRRR is hinting at for later?  STWarning is out from RLX for part of the line right now

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1021 AM EDT Fri May 6 2022

.SYNOPSIS...
An area of low pressure will track through the area tonight.
Thereafter, an upper level low will linger in the vicinity of
the area through the upcoming week.

&&

.NEAR TERM /THROUGH TONIGHT/...

Widespread showers are moving through our region this morning
with embedded moderate to heavy showers. We are seeing rain
rates of 0.10 inches per hour in the light rain with rates up to
an inch per hour in the heavier bands. Our morning sounding had
a PW value of 1.5 inches which is above the 90th percentile
climatology value for this time of the year. A strong convective
line is currently moving through portions central West Virginia
and has a history of producing 2.5 inches per hour rates. This
line is currently on pace to reach the Allegheny front between
17Z and 1830Z this afternoon.

[high risk]

   Seems like there is a good chance of embedded thunder during the evening hours.     While it's a bit uncertain how far north the warm front will get, I agree with SPC that any cells in the warm sector or especially ones that interact with the boundary have potential to spin.     For DC and points north (and probably even a bit further south than that, as I have doubts how far north the warm front will make it before retreating), any storms will be elevated, eliminating the severe potential but allowing for some hopefully nice lightning and thunder.  

[Eskimo Joe]

2 hours ago, yoda said:

@Eskimo Joe maybe this is what the HRRR is hinting at for later?  STWarning is out from RLX for part of the line right now

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1021 AM EDT Fri May 6 2022

.SYNOPSIS...
An area of low pressure will track through the area tonight.
Thereafter, an upper level low will linger in the vicinity of
the area through the upcoming week.

&&

.NEAR TERM /THROUGH TONIGHT/...

Widespread showers are moving through our region this morning
with embedded moderate to heavy showers. We are seeing rain
rates of 0.10 inches per hour in the light rain with rates up to
an inch per hour in the heavier bands. Our morning sounding had
a PW value of 1.5 inches which is above the 90th percentile
climatology value for this time of the year. A strong convective
line is currently moving through portions central West Virginia
and has a history of producing 2.5 inches per hour rates. This
line is currently on pace to reach the Allegheny front between
17Z and 1830Z this afternoon.

Yes. You can see the line segment starting to develop out west towards Cumberland. Even some lightning with it.

[high risk]

36 minutes ago, high risk said:

   Seems like there is a good chance of embedded thunder during the evening hours.     While it's a bit uncertain how far north the warm front will get, I agree with SPC that any cells in the warm sector or especially ones that interact with the boundary have potential to spin.     For DC and points north (and probably even a bit further south than that, as I have doubts how far north the warm front will make it before retreating), any storms will be elevated, eliminating the severe potential but allowing for some hopefully nice lightning and thunder.  

       I think I should have said "this afternoon and evening".     Radar shows very much a rapidly increasingly convective nature to the precipitation across our area.

[mappy]

this weather sucks

[WeatherShak]

       I think I should have said "this afternoon and evening".     Radar shows very much a rapidly increasingly convective nature to the precipitation across our area.

Looks like a nice little thump with embedded lightning incoming from SW Of DC area.

[Rhino16]

It’s been cloudy all day around here. Not sure what that means, but I’m looking forward to at least a little rain.

[Chris78]

Really getting pounded up here in Northern MD with Heavy Rain.

 

[Chris78]

Radar estimates looks like 1 to 2 inches so far across Northern MD. 

Alot more rain to go

[weatherCCB]

59/56

steady light to moderate rain

0.61” since 5am

[yoda]

Tornado Watch #187 basically goes from C NC all the way north to the LWX/AKQ CWA border counties.  CHO and Staunton are included in the watch (Nelson and Albermarle and Augusta counties)  It is in effect until 10pm tonight

https://www.spc.noaa.gov/products/watch/ww0187.html

60/20 tor probs

[yoda]

WATCH COUNTY NOTIFICATION FOR WATCH 187
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
232 PM EDT FRI MAY 6 2022

VAC003-015-125-540-790-820-070200-
/O.NEW.KLWX.TO.A.0187.220506T1832Z-220507T0200Z/

THE NATIONAL WEATHER SERVICE HAS ISSUED TORNADO WATCH 187 IN
EFFECT UNTIL 10 PM EDT THIS EVENING FOR THE FOLLOWING AREAS

IN VIRGINIA THIS WATCH INCLUDES 6 COUNTIES

IN CENTRAL VIRGINIA

ALBEMARLE             CITY OF CHARLOTTESVILLE
NELSON

IN WESTERN VIRGINIA

AUGUSTA               CITY OF STAUNTON      CITY OF WAYNESBORO

THIS INCLUDES THE CITIES OF CHARLOTTESVILLE, CROZET, GREENFIELD,
STAUNTON, STAUNTON, WAYNESBORO, AND WAYNESBORO.