Convective Outlook: What It Is, Chart and Timeline

The Storm Prediction Center (SPC) regularly issues convective outlooks, essential for predicting severe weather events that can significantly impact aviation operations.

These outlooks provide valuable information for local weather stations and the aviation industry, helping them issue alerts for tornadoes, thunderstorms, and other weather-related hazards that can disrupt flights and affect aircraft safety.

Although convective outlooks are considered reliable, their complexity often confuses the general public, pilots, and air traffic controllers.

In this article, we will explain convective outlooks from an aviation perspective, discussing their implications for flights, aircraft safety, and airport operations. By understanding these outlooks, we can better prepare for and respond to severe weather events that impact aviation and ensure safe and efficient air travel.

What is Convective Outlook?

A convective outlook is a weather forecast issued by meteorological organizations, such as the Storm Prediction Center (SPC) in the United States, to anticipate and categorize the potential for severe convective weather events.

These events occur due to the upward movement of warm air, leading to the cooling and condensation of moisture in the atmosphere which results in the formation of clouds, precipitation, and severe weather conditions, such as thunderstorms, tornadoes, and hailstorms.

In aviation, convective outlooks are essential for warning pilots, air traffic controllers, and airport authorities about potential weather hazards that may impact flights, aircraft safety, and airport operations.

By closely monitoring convective outlooks, the aviation industry can take necessary precautions to minimize disruptions and ensure the safety of passengers and crew.

Convective Outlook Chart

Convective Outlook Timeline

Convective outlooks are issued regularly to provide timely and accurate information about the potential for severe weather events.

The timeline of a convective outlook typically consists of four main stages: the Day 1 Outlook, the Day 2 Outlook, the Day 3 Outlook, and the Day 4-8 Outlook.

Each stage covers a specific time frame and provides varying levels of detail, enabling the aviation industry to plan and respond accordingly.

Day 1 Outlook

The Day 1 Outlook covers the risk of severe weather “today” through early “tomorrow morning.”

It is issued five times during the day, starting at 06z (2AM EDT), 13z (9AM EDT), 1630z (12:30PM EDT), 20z (4PM EDT), and 01z (9PM EDT).

This outlook provides the most detailed information about the potential for severe weather, including the location, intensity, and hazards that may impact aviation operations.

Day 2 Outlook

The Day 2 Outlook covers the subsequent 24-hour period following the Day 1 Outlook (tomorrow morning).

It is issued twice daily, starting at 07z (3AM EDT) and 1730z (1:30PM EDT).

This outlook provides a general overview of the expected weather conditions and potential hazards, allowing the aviation industry to make preliminary plans and preparations for potential disruptions.

Day 3 Outlook

The Day 3 Outlook covers the 24 hours following the Day 2 Outlook.

This convective outlook is issued by 0830z on standard time and 0730z on daylight time. It provides an overview of the potential weather hazards and their intensity during this period.

Day 4-8 Outlook

The Day 4-8 Outlook is issued at 10z daily (6AM EDT) in the days following Day 3.

It indicates a 15%, 30%, or higher probability that a severe thunderstorm will occur within 25 miles of any point.

This extended outlook provides insights into the potential risks of severe weather events in the upcoming days, allowing for more long-term planning and preparations in the aviation industry.

Levels of Risk in Convective Outlooks

Convective outlooks provide various levels of risk to indicate the likelihood and severity of potential weather events.

These risk qualifiers help the aviation industry and the public to understand the potential threats and make informed decisions. The main risk levels used in convective outlooks are:

SEE TEXTThis notation is used when a slight risk was considered but not warranted during the forecast. It highlights situations where severe weather is possible but not yet certain.
MRGL (Marginal Risk)A marginal risk represents a limited potential for severe weather events, including isolated severe storms. While the overall threat is relatively low, staying alert and prepared for any possible severe weather occurrences is still important.
SLGT (Slight Risk)A slight risk indicates a high probability of 5 to 29 reports of 1-inch or larger hail, 3-5 tornadoes, or 5 to 29 wind events. There may also be a low/moderate probability of a moderate to high risk being issued later if certain conditions come together.
ENH (Enhanced Risk)An enhanced risk signifies a high probability of at least 30 reports of hail 1 inch or larger, or 6-19 tornadoes, or numerous wind events (30 or more). This level of risk points to a greater likelihood of severe hail, strong tornadoes, or damaging wind events.
MDT (Moderate Risk)A moderate risk represents a high likelihood of severe weather events, such as widespread large hail, numerous tornadoes, or widespread damaging wind. This level of risk indicates a more serious potential for severe weather events.
HIGH (High Risk)A high risk signifies a very high probability of at least 20 tornadoes, with at least two of them rated F3 (or higher), or an extreme derecho causing widespread (50 or more) wind events with numerous higher-end wind (80 mph or higher) and structural damage reports. This level of risk indicates the most severe and dangerous weather conditions.
Thunderstorm Outlook Categories

These risk levels are subject to change as new information becomes available and weather conditions evolve.

The Importance of Convective Outlooks

Convective outlooks are crucial in ensuring the safety of various industries and the public. They provide essential information about potential severe weather events, allowing for informed decision-making and risk mitigation.

One of the primary users of convective outlooks is the aviation industry. Pilots rely on these forecasts to plan safe flight paths and make necessary adjustments in case of predicted severe weather. This helps to ensure the safety of both passengers and crew onboard.

Convective outlooks are vital for preparing for tornadoes, weather fronts, and other extreme weather events. These forecasts enable the issuance of evacuation or shelter-in-place orders, helping to protect lives and property.

However, despite their reliability, public understanding of convective outlooks remains limited. The categories used in these outlooks can be confusing, with terms like “slight risk,” “marginal risk,” and “enhanced risk” often misunderstood by the general public.

Originally, convective outlooks were intended as tools for meteorologists, not for public broadcasts. However, the federal law governing the Storm Prediction Center as a public agency has led to their widespread use in public communications.

To address this issue, there is an opportunity to make convective outlooks more advanced by incorporating additional data, such as marine buoy information, and more intuitive and accessible for public consumption.

Improving public understanding of convective outlooks can help communities better prepare for and respond to severe weather events, enhancing overall safety and resilience.