Bracing for an Intense Storm

Table of Contents

1. Introduction
2. Overview of the Storm Prediction Center's Outlook
3. Features in the Current Weather Pattern
4. Future Radar Forecast
5. High Pressure System and Warm Temperatures
6. Severe Weather Threat on Friday
7. Intensification of the Storm on Saturday
8. Potential Winter Storm and Uncertainties
9. Severe Weather Threat on Sunday
10. Wind Gusts and Sharp Contours
11. Multi-threat Weather Event on Sunday
12. Arctic Air and Jet Stream Patterns
13. Rotation and Tornado Risk
14. Instability and Moisture Content
15. Temperature Patterns and December Heat Wave
16. Conclusion

Overview of the Upcoming Storm and Severe Weather Threat

The United States is bracing for a major storm that is expected to bring significant severe weather and a potential winter storm by the end of the week. The Storm Prediction Center has issued a Day 6 Outlook, indicating a slight risk of severe weather across parts of the Lower Mississippi Valley, Southern Plains, East Texas, Louisiana, and Arkansas. However, the overall risk of severe weather is likely to increase across the region due to the dynamic setup with high shear, instability, and moisture in place.

Features in the Current Weather Pattern

Currently, a storm is entering the Midwest, bringing some snow and rain. In the Southeast, a cold frontal boundary is pushing through, while the Pacific Northwest is experiencing an atmospheric river event with heavy rainfall. This atmospheric river event will contribute to the development of the upcoming large storm later in the week.

Future Radar Forecast

Over the next several days, showers and snow showers are expected in the Midwest and Ohio Valley. However, a high-pressure system will dominate much of the United States, resulting in warm temperatures for most of the week. This pattern will Create what can be referred to as a "December Heat Wave."

Severe Weather Threat on Friday

On Friday evening, a strong low-pressure system is expected to develop in the Northern Plains, bringing high winds and the potential for blizzard-like conditions in northern parts of the United States and Canada. While this storm is significant, it is not the main storm of concern in this forecast.

Intensification of the Storm on Saturday

The main storm of concern is expected to intensify on Saturday, starting in Texas and Southeast Oklahoma and then migrating through parts of Louisiana, Mississippi, Tennessee, Arkansas, and possibly Alabama. This storm will bring both a significant cool-down due to cold air advection and a severe weather threat due to warm air advection.

Potential Winter Storm and Uncertainties

There is some uncertainty regarding the winter storm aspect of this system. As the low-pressure system tracks across the United States, there is a possibility of a wintry mix on the backside, potentially impacting areas like Oklahoma and Northwest Arkansas. However, the exact location and extent of this wintry precipitation are uncertain and can be compared to the cone of uncertainty in hurricane forecasts.

Severe Weather Threat on Sunday

The risk of severe weather is expected to Continue into Sunday, primarily in the Southeast United States. This multi-day severe weather event could see tornadoes, as the low-level jet strengthens and instability persists. However, the level of severity and specific areas affected will depend on the presence of ingredients like instability and moisture.

Wind Gusts and Sharp Contours

The sharp contours on the weather charts indicate that the winds behind the low-pressure system will likely be quite high, with gusts reaching up to 40-50 mph. These strong winds can cause additional hazards and potential damage, including flying trampolines.

Multi-threat Weather Event on Sunday

By Sunday, the storm will transition from a severe weather event to a multi-threat event, including both severe weather and a winter storm aspect. The winter storm part would be on The North and west side of the low-pressure system, potentially affecting areas like Missouri, Arkansas, and parts of Michigan. However, it is important to note that this part of the storm remains uncertain, and precise details may change.

Arctic Air and Jet Stream Patterns

As the low-pressure system races off to the North and east on Monday, some parts of the country can expect a blast of Arctic air on the backside. However, not all areas will experience this cold air intrusion, and the warmer weather will likely return in the following week.

Rotation and Tornado Risk

The lower-level jet pattern indicates potential rotation within the atmosphere, which amplifies the risk of tornadoes. While the low-level jet may not initially be strong on Saturday, it becomes more concerning on Sunday, especially across the southern states along the Gulf Coast. Both Saturday and Sunday pose a significant tornado risk.

Instability and Moisture Content

In terms of instability, there is enough energy in the atmosphere on both Saturday and Sunday to support severe weather. Moisture content, as indicated by dew points, will also contribute to buoyancy, especially in parts of Louisiana, Texas, Georgia, South Carolina, and the Florida Panhandle. These areas should remain alert to the potential for severe weather.

Temperature Patterns and December Heat Wave

Temperature patterns over the next several days will showcase a stark contrast. While some areas in the Northern Plains may experience temperatures 20-30° above average, other regions, stretching from Florida to the Northeast, will have temperatures well below average. This deviation from normal will persist until Saturday when a slight cold blast follows the low-pressure system. However, this cooler weather is not expected to last long, and warmer conditions will return in the following week.

Conclusion

In conclusion, the United States is preparing for a significant storm that could bring severe weather, including damaging winds, large hail, and tornadoes, as well as a potential winter storm. While the exact details and affected areas may change, it is crucial for residents in the highlighted regions to stay informed and prepared for this multi-threat weather event. Stay tuned to local forecasts and heed any warnings or advisories issued by authorities.