Tuesday, February 13, 2024 — Afternoon Forecast
Tuesday Night: Mostly Clear. Low: 36
Wednesday: Sunny. High: 65
Wednesday Night: Mostly Cloudy. Low: 45
Thursday: Partly Cloudy. High: 49
Thursday Night: Increasing Clouds. Low: 35
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Discussion:
Another round of unseasonable weather this week! Currently, sunny sky conditions dominate the region, and this will persist through tomorrow afternoon. Southerly winds and sunny sky conditions will allow temperatures to reach mid-60s tomorrow afternoon. Wednesday night will see an increase in cloud cover, and a cold front will bring temperatures back to more seasonable conditions by Thursday afternoon.
-Yost
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Forecasters: Yost, Thee
Date Issued: 02/13/2024 5:00PM CST
Technical Discussion:
Key messages:
- Unseasonable weather returns this week with temperatures reaching mid-60s by Wednesday.
- Cold frontal passage Thursday morning brings a quick return to seasonal conditions.
Visible satellite imagery displays widespread, sunny sky conditions in the central CONUS associated with a strong anticyclone. Current surface analysis depicts this feature centered in eastern Texas, with a broad WAA regime setting up to the west of the system. Strong WAA and sunny sky conditions allowed temperatures across the state to reach upper-50s, low-60s. Additionally, a stationary front drapes across the border of MO and Iowa, associated with a cyclone on the lee-side of the Rockies. North of the stationary front, cloud cover is much more abundant but will remain outside the CWA. With the NAM and GFS models representing surface observations accurately, both models were used in tandem for this forecast.
Currently, the upper-levels display dominant zonal flow across the CONUS, with very subtle ridging. An associated surface anticyclone in Canada brings in the northerly winds, north of the stationary stationary front. At the same time, a secondary anticyclone in the south brings in southerly flow, south of the front. Late tonight into tomorrow morning, a low-amplitude shortwave will quickly traverse the Central Plains and strengthen the aforementioned cyclone on the lee-side of the Rockies. This strengthening can be seen by noting the tightening pressure gradient in the wind field across the Central Plains. The shortwave will begin shifting the cyclone towards the region by tomorrow afternoon, which will generate a stronger wind field, and increased WAA. Likewise, the low will track north in MO, through Iowa, and a cold front will drape to the south of the low center. With the arrival of moisture being confined to late in the evening, sky conditions are forecast to be sunny throughout Wednesday. With strong WAA, and sunny sky conditions, temperatures on Wednesday will be much above the average (avg. high 44).
By Late Wednesday night, the shortwave will pivot across the CWA and induce subtle PVA. The GFS and NAM have high-consensus in the timing of this feature. With that said, forcing for ascent will be weak, and moisture content will be lack-luster. A strong low-level jet can be noted Wednesday night, with 50kts of flow over the CWA. However, sounding analysis suggests Planetary Boundary Layer (PBL) moisture not being sufficient enough for precipitation. However, we cannot rule out a small chance (10-20%) of measurable accumulation. With this said, the arrival of the cold frontal boundary Thursday morning will advect cool, dry air into the region. The thermodynamic profile displays enhanced air mass modification by 18Z Thursday, showing dominant dry air intrusions and cooler surface temperatures. This would indicate a slow return to seasonal weather and decreased cloud cover throughout the day on Thursday.
The main synoptic wave, downstream of the shortwave, will start to dig south on Thursday evening. This will induce a secondary cyclone to develop on the lee-side of the Rockies. Likewise, the upper-level trough will have stronger forcing for ascent compared to Wednesday night. The biggest difference between this system and the last one is the track. The surface cyclone will meander east-southeast throughout the early morning on Friday and center over the CWA by the early afternoon. An increase in cloud cover is expected Thursday night ahead of this system. Future forecasters should keep these features in mind when analyzing the system Friday afternoon for the potential of rain.
-Yost