Lexington Weather

Lexington, Massachusetts, USA

70°F

5/17/2024 12:42pm

Lexington Conditions: Partly cloudy
Temperature: 70.3°F / 21.3°C
Dew Point: 56.7°F
Relative Humidity: 62%
Wind: NE 2 mph, 10-min avg: 2 mph, gust: 9 mph
Barometer: 29.93 in Steady
Visibility: 10 miles
Rain Today: 0.00 in

Area Forecast Discussion
for North Platte, NE

        
000
FXUS63 KLBF 120526
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
1226 AM CDT Sun May 12 2024

.KEY MESSAGES...

- Daily high temperatures remain near seasonal to above 
  seasonal through the work week. Overnight lows mostly in the 
  40s, limiting any frost concerns this week. 

- Widespread chances of showers and thunderstorms tomorrow 
  afternoon, with little to no severe weather expected. 

- The best chance for showers and thunderstorms comes Tuesday
  night into Wednesday morning, with some question on the
  potential for severe storms. Slight chances (less than 30
  percent) of showers persist most days of the week.

&&

.SYNOPSIS...
Issued at 245 PM CDT Sat May 11 2024

Upper air analysis and satellite imagery place an upper level cut 
off low over northern Arizona. Further west, another wave is noted 
across the northern Pacific Ocean, with a ridge off the West Coast 
and a trough behind it. At the surface, high pressure is the 
dominant feature over the Plains. The major weather story has been 
the recent space weather activity, with the aurora visible last 
night and an ongoing G4 geomagnetic storm this morning and early
afternoon.

&&

.SHORT TERM /THROUGH MONDAY/...
Issued at 245 PM CDT Sat May 11 2024

Tonight, as the upper level low slowly tracks east, areas of showers 
and potentially thunderstorms are possible across portions of 
southwest Nebraska. The most likely area for rain tonight is along 
and south of a line from roughly Oshkosk to Broken Bow. Given the 
very limited forcing, no severe weather is expected with 
thunderstorms this evening. 

The other big weather story this evening remains the active space 
weather that caused aurora sightings across Nebraska and a fain 
amount of the United States last night. The ongoing solar activity 
has been quite intense, with possible impacts on radio and GPS. The 
Space Weather Prediction Center has extended their warning for 
Geomagnetic K-Index of 7 or greater, which may create an additional 
chance to see the aurora across western and north central Nebraska 
tonight. However, the biggest challenge will be sky cover this 
evening. Clouds are expected to move in this evening, with possible 
precipitation, again along a line from Oshkosh to Broken Bow. Areas 
to the north may be a bit more lucky with sky conditions, but will 
merit keeping an eye on for those hoping to get another chance at 
the aurora. The latest space weather information and aurora forecast 
can be found at swpc.noaa.gov. 

Chances of showers and thunderstorms continue on Sunday through 
Monday morning, as the upper level low is closer in proximity to the 
south and a cold front sweeps down from the north. Though 
thunderstorms are expected, the severe potential is low at this 
time, with marginal amounts of CAPE and fairly weak shear values. 
Current CAM guidance keeps storms tomorrow afternoon rather spotty 
in nature, keeping expected rain totals fairly limited, generally 
under one quarter of an inch. However, showers and storms may 
produce some locally heavier amounts, with expected PWAT values 
ranging from one half inch to one inch.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Issued at 245 PM CDT Sat May 11 2024

The upper air pattern remains fairly progressive over the course of 
the week. By Monday afternoon, the upper level low is expected to be 
over eastern Kansas, with nearly zonal flow aloft over wester and 
north central Nebraska. The nearby upper level low may still provide 
enough forcing for some light showers, mainly across southwest 
Nebraska and the Sandhills, however, guidance remains fairly 
spotty on this. Ensembles are a bit more optimistic for 
precipitation greater than or equal to one one-hundredth of an 
inch (around 90 percent chances across), but limited to the 
southern portion of the state for one tenth of an inch or 
greater. 

By Tuesday, the upper level pattern supports the best chance of 
showers and thunderstorms next week. An upper level shortwave begins 
to deepen across Wyoming. A surface system tracking through the 
region late Tuesday afternoon into the early morning hours of 
Wednesday will be the focus for showers and thunderstorms. For now, 
the severe weather threat is still a bit in question, but given the 
support and forecast soundings, will definitely be worth keeping an 
eye on. Though there is still some variance in the individual 
models, there has been some consensus in a narrow tongue of CAPE 
nearly along Highway 83, with just enough shear support to support 
severe convection. However, there still is some question model to 
model in how much CAPE and shear will be available. 

After the shortwave trough lifts to the north, the upper level 
pattern remains mostly to the north and south of the region. There 
is still a little uncertainty in the actual track of the upper level 
flow, and ensembles pick up on that uncertainty. Ensembles highlight 
that chances of measurable precipitation for the rest of the week 
remain generally in the 20 to 30 percent range. With the upper level 
pattern remaining fairly progressive, daily highs should remain 
nearly seasonal to above seasonal throughout the week. For 
reference, seasonal daily highs are in the low 70s across the 
region. As for overnight temperatures, generally expected 
temperatures will be in the 40s throughout the week, which will 
limit the chances for frost across the region.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1226 AM CDT Sun May 12 2024

An area of low pressure approaching the High Plains will result
in scattered rain showers and somewhat lower ceilings (~5kft)
today. Precipitation spreads into southwest Nebraska this
morning, while new development occurs across the Sandhills
during the afternoon. Conditions should hold at VFR, although
brief interruptions due to lower visby or cigs will be possible
in heavier rain. Meanwhile, south/southwest winds this morning 
will transition to northeasterly midday (north/VTN) or this 
evening (south/LBF).


&&

.LBF WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SYNOPSIS...Richie
SHORT TERM...Richie
LONG TERM...Richie
AVIATION...Snively