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070220 Forecast

July 2, 2020Uncategorizedadmin

Independence Day Holiday Period

*Mid-Summer conditions will feature warmer than average temperatures and many dry hours during the Independence Day Holiday period.

Any thunderstorm that develops during the Holiday period could become briefly and locally strong to severe, with dangerous lightning, gusty winds, and downpours of rain. Coverage is expected to generally remain low.

Chances for hit-miss showers and thunderstorms will remain low through Saturday, with somewhat better chances for afternoon and evening activity during Sunday and Monday of the Holiday period.

July Opens Amid Warmer-Drier Trend

**European Model_850 MB Temperature Anomaly Forecast_3-8 July 2020**

A warmer than average temperature trend is being predicted by forecast models during the first half of July across much of the continental USA.

**European Model_850 MB Temperature Anomaly Forecast_7-12 July 2020**

A trend toward somewhat cooler temperatures toward mid-July is currently being indicated, driven by a possible increase in showers & thunderstorms.

A drier than normal rainfall trend, in general, is being forecast by models during the first couple weeks of July.

Actual rainfall amounts, however, will undoubtedly vary significantly across the region (reference June).

**European Ensemble Mean_500 MB Height Anomaly Forecast_7-12 July 2020**

Recap Of June 2020

It should be noted that following maps use model interpolation in between actual data collection sites, such that local conditions may be different than represented (especially in complex terrain).

June 2020 featured near to slightly below average temperatures and rainfall amounts that varied from much below average to much above average.

**Mean Max Temperature Versus Average_June 2020**

The coolest temperatures, relative to longer-term averages, were experienced during the day.

**Mean Min Temperature Versus Average_June 2020**

June Precipitation Totals

High Country (Upper Elevations)

**High Knob Lake Basin of High Knob Massif_24 June 2020**

Snowshoe Mountain (WV): 8.46″
(+3.62″)

Mount LeConte (TN): 8.28″
(+0.98″)

Big Cherry Lake Dam (VA): 7.48″
(+1.35″)

Canaan Mountain (WV): 5.91″
(+0.67″)

Beech Mountain (NC): 5.72″
(+0.70″)

Eagle Knob (VA): 5.65″

Grandfather Mountain (NC): 5.36″
(-0.95″)

Newfound Gap (TN): 5.34″

Mount Mitchell (NC): 4.95″
(-0.40″)

Black Mountain (KY): 4.76″

Boone 1 SE (NC): 4.21″
(-0.85″)

Burkes Garden (VA): 3.97″
(-0.25″)

Middle-Lower Elevations

Wytheville (VA): 7.15″
(+3.58″)

Roan Mountain 3 SW (TN): 4.10″

Grundy (VA): 3.86″
(-0.64″)

Richlands (VA): 3.52″
(-0.43″)

Wise 1 SE (VA): 3.30″
(-1.16″)

Saltville 1 N (VA): 3.08″
(-1.07″)

Clintwood 1 W (VA): 2.91″
(-1.88″)

Tri-Cities (TN): 2.75″
(-1.15″)

Lebanon (VA): 2.57″
(-2.01″)

Abingdon 3 S (VA): 2.33
(-1.73″)

Rogersville 1 NE (TN): 2.06″
(-1.75″)

062520 Forecast

June 25, 2020Uncategorizedadmin

ALERT For The Potential Of Heavy To Locally Excessive Rainfall Amounts

Interactive Lightning And Storm Tracking Doppler

Folks living and driving (and hiking) near streams and in low-lying, flood-prone locations will need to remain alert and closely monitor changing weather conditions through coming days.

Some Thunderstorms Could Be Strong To Locally Severe Into Sunday-Monday

Interactive 850 MB Flow Field

Observe flow field streamlines from the Atlantic Ocean across the Gulf of Mexico into the southern Appalachians in a clockwise flow around High pressure centered near Florida. In addition, there is some concern that Saharan Dust could contribute some CCI (cloud condensation nuclei) to further enhance rainfall making capability as air is lifted by a combination of dynamics and orographics through a deep vertical column.

Roles Of Mineral Dust As Cloud Condensation Nuclei

Efficiency of Dust Storm Particles As CCI

Measurement Of CCI And Droplet Activation Kinetics

The role of dust as CCI is complex, with varied results depending upon many factors, not the least of which is location and particle sizes. CCI as a linkage between different climate system components, however, is clear and more research is needed to better understand these connections and the role dust plays from weather to ecosystem biodiversity (e.g., Saharan dusting acting to fertilize the Amazonian Rainforest).

Influx of tropical moisture around High pressure toward the south will combine with a upper air setting favorable for upward vertical motion to support a heavy to excessive rainfall potential.

**Excessive Rainfall Potential_8 AM Sunday to 8 AM Monday_28-29 June 2020**

Interactive 500 MB Flow Field

A very moist atmosphere will combine with disturbances passing through a developing W-NW flow field to trigger clusters of showers and thunderstorms into early next week.

**Excessive Rainfall Potential_8 AM Monday to 8 AM Tuesday_29-30 June 2020**

Some thunderstorms could be strong to severe on Sunday into Monday, with two main modes being watched for the severe potential:

1). Mesoscale Convective Systems that may develop in W-NW flow will have the potential to support strong-severe convection

2). Localized convection could turn severe, especially if breaks develop in the rainfall pattern to enhance instability associated with daytime heating.

**Storm Prediction Center Risk Regions_8 AM Sunday to 8 AM Monday**

Mesoscale, higher resolution models, are showing wide variations in rainfall with potential for locally excessive amounts and flash flooding.

**NAM 3 KM Model_Total Rainfall Forecast_To 8 PM Monday**

The placement of heaviest rainfall amounts continue to vary among forecast models, and from run-to-run on the same model, but a clear signal for significant rain amounts is being displayed on all models.

**WRF 5 KM Model_Total Rainfall Forecast_To 8 AM Monday_29 June 2020**

Synoptic-Scale Weather Setting

**European Ensemble Mean_500 MB Height Anomaly Forecast_26 June-1 July**

A somewhat unusual pattern featuring heat ridge formation over the Great Lakes and southeastern Canada will cause temperatures, relative to long-term average, to skew hot in the north country to contrast with near average conditions over the SE USA and southern Appalachians.

**European Model_850 MB Temp Anomaly Forecast_26 June-1 July 2020**

A boundary separating seasonally hot air to the north from seasonal air toward the south will generate clusters of showers-thunderstorms.

**NAM 12 KM Model_Total Rainfall Forecast_To 8 PM 30 June 2020**

The position and movement of the boundary over time will help to dictate where heaviest rains fall. Models are currently in disagreement.

**GFS Model_Total Rainfall Forecast_To 8 AM on 2 July 2020**

Soil moisture has decreased significantly from the end of March in many places (especially amid high June sun angles).

**Soil Moisture Anomaly Since 31 March 2020**

Due to excessive amounts of precipitation for this point in a year, soil moisture remains on the surplus side, especially in wettest places.

High Knob Massif Precipitation Update (23 June 2020)

**CPC Calculated Soil Moisture_24 June 2020**

Moving Forward

June 25, 2020Uncategorizedadmin

Black Lives Matter Statement

061820 Forecast

June 18, 2020Uncategorizedadmin

ALERT For Local Downpours Beneath Slow Moving (Hit-Miss) Showers And Thunderstorms

Slow moving showers and local thunderstorms will continue to produce downpours into this weekend.

Interactive Real-Time Lightning And Storm Tracker

The potential for excessive localized rainfall will continue as a upper-level low slowly dissipates.

**European Model 500 MB Heights_8 AM Thursday_18 June 2020**

Interactive 500 MB Flow Field Streamlines

A new upper-level low will drop into the Great Lakes and eastern USA into next week, following weekend warming with lower rain chances on Sunday.

**European 51-Member Ensemble_500 MB Anomaly Forecast_23-28 June 2020**

This will continue and enhance rainfall chances next week as air temperatures trend from near to above average in early week to near and below average during mid-late next week.

**European Model_850 MB Temp Anomaly Forecast_19-24 June 2020**

An enhanced surge of deep, tropical moisture is being monitored for later in this forecast period that could support widespread heavy rainfall & storms.

**European Model_850 MB Temp Anomaly Forecast_23-28 June 2020**

Stay tuned for later updates.

060520 Forecast

June 5, 2020Today's Forecast Archiveadmin

Weather Headlines

Some thunderstorms could become strong to locally severe, especially by later Wednesday into early hours of Thursday ahead of a strong front. Locally heavy rains will be possible from Tuesday evening through Wednesday evening.

**SPC Risk Regions_8 AM Wednesday to 8 AM Thursday_10-11 June 2020**

*Localized, hit-miss activity Tuesday will give way to more widespread action along a cold front trailing from deep low pressure to the north Wednesday.

Interactive Doppler Radar

Cooler And Wetter Trend Upcoming

*Conditions will turn significantly cooler from Thursday into this weekend as upper air troughing develops once again, with coolest air (relative to average) centered over the Great Lakes initially.

**European Model_850 MB Temp Anomaly Forecast_11-16 June 2020**

This will mark the beginning of a cooler and wetter weather pattern that will become dominant from this weekend through much of next week (*).

*It should be noted that model trends are divided for next week, with some ensemble members showing above average rainfall while others predict below average rainfall.

The track and development of low pressure in upper levels of the atmosphere will help determine rainfall amounts. Either way, until a prolonged dry pattern does develop the flash flood risk will remain higher than average (especially in locations having had the greatest precipitation amounts this year).

An elevated flash flood risk will continue and need to be closely monitored.

Anomalously wet conditions observed during the past 6+ months have created flashy conditions in locations within and near the High Knob Massif, but the entire region will likely need to closely monitor conditions given current forecast trends.

**European Model_850 MB Temp Anomaly Forecast_14-19 June 2020**

Local flash flooding observed in recent weeks could become more problematic (impacting more people). Stay tuned for later updates into next week.

**European Ensemble Mean_500 MB Height Anomaly Forecast_14-19 June 2020**

Previous Update

*ALERT For Elevated Stream Levels Along Big Stony Creek (Including Devil Fork) And The South Fork Of Powell River Into Saturday

**Observed Stream Levels Since 1 May 2020**

Torrential rain producing showers and localized thunderstorms have dropped a general 1.50″ to 3.00″ of rain between Maple Gap and Osborne Gap this afternoon, including the peaks of Eagle Knob, High Knob, Little Mountain Knob, Huff Rock Knob and Thunderstruck Knob of Powell Mountain.

Some of the headwater creeks impacted include: Big Stony Creek, Benges Branch, Chimney Rock Fork, Clear Creek, Cove Creek, Devil Fork, Glady Fork, Lost Creek, Robinette Branch, South Fork of Powell River and Straight Fork.

Reference Early Summer 2020_High Knob Massif

**High Knob Lake Recreation Area_High Knob Massif_Summer 2020**

Check for updated precipitation totals for 2020, including early June, at the above link during the next couple of days.

Warmer Then Cooler As Cristobal Passes

**European Ensemble Mean_500 MB Height Anomaly Forecast_6-11 June 2020**

Large-scale sinking air will renew warming as Cristobal moves through a weakness in an upper air ridge pattern across the eastern USA into early next week. This is expected to initially lower rain chances and increase air temperatures across the mountains and adjacent regions.

**European Model_850 MB Temperature Anomaly Forecast_6-11 June 2020**

Shower & thunderstorm chances will increase along a cold front attached to Cristobal remnants by the middle of next week. Significant cooling will then occur with upper air trough formation by later next week-weekend.

**European Ensemble Mean_500 MB Height Anomaly Forecast_10-15 June 2020**

A W-WNW flow pattern will need to be monitored for the potential of thunderstorm cluster development heading into the middle of June, which will tend to form around a developing heat dome anchored over the central Plains.

**European Model_850 MB Temperature Anomaly Forecast_10-15 June 2020**

Some of the wettest and most stormy conditions are expected to develop along a thermal gradient between blazing heat and unseasonably cool air, such that the ultimate position of this horizontal temperature gradient will be a key factor in where clusters of showers and thunderstorms develop. The placement of this thermal gradient, and heat dome core, is yet to be precisely determined.

Stay tuned for updates as details of this new pattern become more clear.

053020 Forecast

May 30, 2020Today's Forecast Archiveadmin

ALERT For The Potential Of Locally Strong-Severe Thunderstorm Development Today Into This Evening ( 4 June 2020)

**Severe Risk Regions_8 AM Thursday to 8 AM Friday_4-5 June 2020**

Weather Headlines

*Unseasonably cool air Sunday into early Monday is expected to generate a gorgeous conclusion to spring and start of Meteorological Summer.

**NAM 12 KM Model_850 MB Temp Forecast_8 AM Sunday_31 May 2020**

Reference Early Summer 2020_High Knob Massif for more details.

**Beginning Of Meteorological Summer_High Knob Lake Basin**

The coldest opening to a June on record in Wise was in 1966 with 31 degrees (that same morning featured 30 degrees in Burkes Garden).

The coldest opening to a June on record in Burkes Garden was in 1930 with 26 degrees, while the coldest on record in Canaan Valley (WV) reached 24 degrees in 1960.

**Wise Temperatures For 1 June_1973-2019**

While all-time record mins will remain safe, the coldest temperatures in several decades will be likely on early Monday this year, with coldest temperatures in the 30s amid high mountain valleys (widespread 40s to around 50 degrees within many other locations).

**Burkes Garden Temperatures For 1 June_1973-2019**

Light gradient winds, clear skies, and a unseasonably large 850 MB dewpoint depression will generate frost in cold air collecting basins at upper elevations from the High Knob Massif to Canaan Valley.

Northern Canaan Valley Frost Pocket

The northern frost pocket site in Canaan Valley, West Virginia will have a chance to drop into the 20s and approach the all-time record MIN for June 1 in Canaan Valley, and the all-time MIN for the month, which can be followed at this link.

**NAM 12 KM Model_850 MB Wind Streamline Forecast_8 AM Monday_1 June**

Humid-Unsettled Pattern Ahead

Developing upper air ridging across the USA will feature a separation in the ridge over the Southeast and Gulf Of Mexico, increasing the opportunity for unsettled conditions and possible tropical develop-ment over the Gulf by later in this period.

**European Ensemble Mean_500 MB Height Anomaly_2-7 June 2020**

A dramatic transition from unseasonably cool to unseasonably warm air will occur as this pattern develops, with hit-miss to widespread showers and downpours in thunderstorms becoming likely.

**European Model_850 MB TEMP Anomaly Forecast_2-7 June 2020**

052520 Forecast

May 25, 2020Today's Forecast Archiveadmin

Weather Headlines

*High water levels will continue along Big Stony Creek, Little Stony Creek, South Fork of Powell River and other steep creeks draining the high country along the Wise-Scott-Lee border area, as well as portions of Black Mountain, into today (Monday, 25 May 2020).

*A warm, moist air mass will dominate the mountain region through this week with hit-miss showers and downpours in thunderstorms.

The potential for local high water will continue with development of torrential rain producing showers and thunderstorms. Folks living and driving along streams and within flood prone locations should remain alert for the potential of rapid water level rises. This includes those hiking in remote locations of the High Knob Massif and Jefferson National Forest.

Interactive Doppler Radar

*An increase in moisture in advance of a strong cold frontal boundary, which may in part be contributed to by tropical moisture transport, will increase the coverage of showers-thunderstorms later this week into the early weekend.

**ECMWF Ensemble Mean_500 MB Height Anomalies_Days 1-6**

*Much cooler air is being monitored for later this weekend into early next week during the transition into Meteorological Summer and the month of June.

**ECMWF Model_850 MB Temperature Anomaly_8 PM on 31 May 2020**

051420 Forecast

May 14, 2020Today's Forecast Archive, Uncategorizedadmin

Weather Headlines

*Warm and more humid conditions will offer a chance for hit-miss showers or thunderstorms through this weekend.

Interactive Doppler Radar

*A upper-level low will dominate weather conditions across the southern-central Appalachians through the upcoming work week.

**European Model_500 MB Height Anomaly Forecast_18-23 May 2020**

Interactive 500 MB Flow Field

Locally heavy to excessive rainfall amounts will be possible, but upper lows are notoriously difficult to predict exactly where bands forming around their swirling circulation will develop.

Waves rotating aloft around upper-level lows tend to support low-level convergence zones at the surface, with these being difficult to predict in advance of their development. Since it is impossible for air to go downward into the ground, low-level convergence mandates rising air with subsequent cooling and condensation to support precipitation formation.

If the upper low remains stationary from one day to the next, corridors that receive heaviest rain amounts during day 1 may again be impacted on day 2, especially if over terrain locations where tree leaves have fully matured and evapotranspiration is running at a maximum level to support a positive feedback for wetness.

If the upper low moves from one day to the next, the corridor that receives heaviest rainfall amounts also tends to move as the low-level convergence becomes focused, or enhanced, along a new corridor.

Interactive Surface Streamline Flow Field

The potential for heavy to excessive rainfall is enhanced if these upper-level low generated convergence zones (where air rises) phase with orographic forcing and become superimposed on air flow trajectories which are naturally forced to rise by terrain barriers.

Interactive 850 MB Flow Field

**NAM 12 KM Model_Total Rainfall Forecast_12z Saturday Run**

Large run-to-run model variations for any given spot indicates the uncertainty for a given spot, but persistent replication of heavy-excessive amounts indicates that some places will tend to get much more rain (with possible high water issues) than other locations this upcoming week.

**NAM 12 KM Model_Total Rainfall Forecast_18z Saturday Run**

NOWCasting is a favored term used to describe this type of forecast scenario, where heavy rain potential is best resolved once rain bands begin forming during any given day around the upper low.

**European Model_850 MB Temp Anomaly Forecast_18-24 May 2020**

Near average to below average temperatures will occur mainly due to clouds and rainfall, impacting maximum temperature most relative to average.

050720 Forecast

May 7, 2020Today's Forecast Archiveadmin

Weather Headlines

Reference May 1989 Weather for a historic look at May cold.

*Another significant wave of rain will give way to much colder air Friday night into Saturday, with a change to snow and mixed precipitation.

*A dusting up to 2″ of snow accumulation will be possible, mainly at elevations above 3000 feet into early Saturday (locally higher amounts will be possible on peaks above 4000 feet).

Air temperatures will vary from upper 10s to lower 20s (with much colder wind chills along ridges) on highest peaks to lower 30s in warmer valleys.

Wind chill factors will drop into single digits above and below zero, especially in gusts, along highest mountain ridges during Friday night into Saturday AM. Bitterly cold for early May.

*Good radiational cooling conditions will allow coldest temperatures Saturday night into early Sunday to develop within mountain valleys, with widespread below freezing temperatures.

*An additional push of unseasonably cold air will again set the stage for more freezing to below freezing conditions centered on 12-13 May 2020.

May 1989 Weather

May 7, 2020Historical Weather Archiveadmin

May is no stranger to cold air, with the setting in 1989 similar to what is being observed currently (in 2020) when a wet and colder than average May followed a mild and much below average snowfall regime during the 1988-89 winter season.

**500 MB Height Anomaly Pattern_May 1989**

Flash flooding became a deadly issue during early May 1989, with the following written in my weather journal during this time (1989 was a wet year):

Around 8:00 PM, 5 May 1989: A family of three were plunged into swollen Garden Creek of Levisa Fork River after the Van they were driving collided with a coal truck on State Route 624. They were quickly swept downstream into the raging Levisa Fork. All three were lost and drown. One body was recovered 5-6 miles downstream, another in Grundy, and the third victim was eventually discovered 30 miles downstream, north of Fishtrap Lake in Pike County, Kentucky. Truly, a terrible tragedy!

**Official_National Weather Service Record_Clintwood VA**

Flash flooding occurred along the South Fork of Powell River within the Cracker Neck to Big Stone Gap section of Wise County, the Guest River in Wise County, the South Fork of Pound River in northern Wise County, and the Russell Fork River (among others) in Dickenson County.

Additionally, numerous mud-rock slides were reported.

Heavy rain accompanied a strong southward dip in the jet stream, with a surge of unseasonably cold air that changed precipitation into snow.

**1 Mile SE of Wise Courthouse_Campus of Clinch Valley College**

The observation time was 1700 hours (5 PM) daily in Wise, such that only 1″ remained on the ground at 5 PM on 7 May 1989 (increase zoom factor of page for best chart viewing).

Snow fell heavily into morning hours of May 7:

As the midnight hour passed into 7 May a wintry mix falling in mountain valleys began changing into large, fluffy flakes of snow as air temperatures reached the freezing mark. By 4:30 AM on 7 May, moderate-heavy snow was falling across the mountain area (from the High Knob Massif northward).

Snowfall rates intensified around dawn, with the break of sunrise appearing to be a mid-winter blizzard had it not been for spring vegetation.

Snowfall totals reached 2.3″ in Clintwood, 3.3″ in Wise, and 4″ or more at upper elevations within the High Knob Massif.

*This snow was so majestic, as adhesive crystals intermingled with a spectrum of hues representative of the spring forest, that it was part of the reason I was inspired to become a nature photographer.

Clearing skies allowed the air temperature to drop below freezing in Clintwood prior to midnight on 7 May, with high humidity in wake of rain and snow resulting in significant freeze damage (especially at lower-middle elevations which had more advanced spring growth).

Visible freeze damage was observed in the following tree species (to note a few impacted):

Hickory
(Carya spp.)

American Beech
(Fagus grandifolia)

Tulip-poplar
(Liriodendron tulipifera)

Magnolia
(Magnolia spp.)

Sourwood
(Oxydendrum arboreum)

Black Locust
(Robinia pseudoacacia)

Sumac
(Rhus spp.)

Sassafras
(Sassafras albidum)

Visible freeze damage remained evident on species such as American Beech into June, although I do not recall it being as severe and impressive as the forest browning which occurred during May 2005.

Min temperatures during the 7-8 May period reached 23 degrees within Burkes Garden Basin, 26 degrees in Clintwood, 27 degrees in Canaan Valley Basin, 28 degrees in Wise, and 30 degrees in the Great Valley at TRI (tying previous records for all-time May coldness in the Tri-Cities of northeast Tennessee).