Yes, you read the title of this article correctly. Many joked that the Central Plains states were a new lake and that is actually fairly accurate assessment. In May, the state of Kansas averaged 10.26 inches across all official weather recording stations. This was over 240% of the 30-year normal of 4.12 inches statewide.
By the numbers
May is historically one of Kansas’ wettest months of the year. The warm season consisting of May through August is climatologically the wettest period of the year. Maximums typically occur in one of those months depending on your location in the state. With over 125 years of data, the 10.26 inches of rain averaged across the state in May surpassed the previous 8.79 inches recorded in 1995 (Table 1). Not only did it surpass the record for May, but also the record for the wettest month ever. That previous record was 9.36 inches in June 1951.
Table 1. Top 10 highest rainfall totals for the month of May over the last 125 years. (Source: Kansas Weather Data Library).
|
Rank |
Year |
Precipitation Average Statewide (inches) |
|
1 |
2019 |
10.26 |
|
2 |
1995 |
8.79 |
|
3 |
2015 |
8.28 |
|
4 |
1903 |
7.78 |
|
5 |
1935 |
7.35 |
|
6 |
1938 |
7.22 |
|
7 |
1915 |
6.71 |
|
8 |
1982 |
6.63 |
|
9 |
1957 |
6.52 |
|
10 |
1981 |
6.43 |
As mentioned in previous articles, increased moisture has been the story since October 2018. This has not only made it difficult for agriculture but set the stage for historic flooding in many parts of the state. The climatological average precipitation for the year to date from January to the end of May is 10.58 inches. This year for that period Kansas has averaged 16.65 inches, by far the most for this time period on record. For reference, 1993 was the 11th most from January through May with 13.89 inches.
Countless locations in the state, especially in central/eastern areas received tremendous amounts with 20 stations recording over 20 inches (Table 2) in May alone. In most places, this was over half their normal yearly precipitation. The highest daily rainfall was as much over nine inches! Horton recorded 9.42 inches (ASOS) and Rock 3 SW (COOP) had 9.08 inches to take the top daily totals in the state.
Table 2. Stations with May monthly totals over 20 inches of rain in Kansas. (Source: Kansas Weather Data Library).
|
Rank |
Year |
Network |
Precipitation Total for May (inches) |
|
1 |
ROSE HILL 2.7 ESE |
CoCoRaHS |
30.08 |
|
2 |
ROCK 3 SW |
COOP |
26.14 |
|
3 |
EUREKA 0.9 NW |
CoCoRaHS |
25.21 |
|
4 |
WINFIELD 7.9 W |
CoCoRaHS |
24.71 |
|
5 |
AUGUSTA 1.0 S |
CoCoRaHS |
24.03 |
|
6 |
MULVANE 4.3 WSW |
CoCoRaHS |
23.02 |
|
7 |
HORTON |
COOP |
22.00 |
|
8 |
YATES CENTER |
COOP |
21.93 |
|
9 |
WELLINGTON |
COOP |
21.80 |
|
10 |
WELLINGTON 1.3 W |
CoCoRaHS |
21.80 |
|
11 |
BELLE PLAINE 4 W |
COOP |
21.79 |
|
12 |
POTWIN |
COOP |
21.75 |
|
13 |
NORTONVILLE |
COOP |
21.48 |
|
14 |
FARLINGTON 0.8 NNE |
CoCoRaHS |
20.92 |
|
15 |
MCCUNE 1.6 NW |
CoCoRaHS |
20.89 |
|
16 |
PITTSBURG |
COOP |
20.56 |
|
17 |
Haysville |
Kansas Mesonet |
20.40 |
|
18 |
WINFIELD 5.9 SW |
CoCoRaHS |
20.38 |
|
19 |
COLUMBUS |
COOP |
20.17 |
|
20 |
OSAGE CITY 5.2 SW |
CoCoRaHS |
20.06 |
A pattern for moisture
Despite spring typically being a dynamic weather pattern with changing weather across the nation, this year was a bit different. A very persistent ridge set up mid-May across the eastern U.S. (Figure 1). This developed a summer-like pattern for those in the southeast. They experienced very dry conditions and an extensive heat wave not typical for this early in the year.
Further west, a persistent ridge across the western U.S. was the result of a strong, buckling jet stream, very anomalously strong for this time of year (120-160 kts), something more typical of February. Unfortunately, the placement of this dip/trough is ideal for advecting moisture northward from the Gulf of Mexico northward into the Central Plains. With the abundance of moisture and persistence in the pattern, widespread flooding (and severe weather resulted).
Figure 1. An upper level map showing the persistent dip in the jet stream across the western half of the U.S. and a rise (ridge) over the east. Surface featured a persistent low pressure (blue L) across the southern High Plains and a persistent high pressure (red H) in the southeast. Corresponding flow around these surface features transported Gulf, tropical moisture northward into the Central Plains. (Source: weather.uwyo.edu/upperair/uamap.shtml)
Impacts on rivers and lakes
The overall pattern in Kansas, as well as Nebraska, Iowa, Missouri and Oklahoma, has resulted in widespread flooding. At the end of May, several U.S. Army Corp of Engineer lakes were at or near flood capacity (Figure 2). Despite some dry days to begin June, the hydrological system is still near capacity. Flooding in low-lying areas is likely to continue and river levels are likely to remain high through June and possibly into August. The Climate Prediction Center’s outlook for the summer (June, July, and August) continues to favor a wetter-than-normal pattern for the Central Plains.
Figure 2. Percent of Flood Control Pool at various lakes/reservoirs in Kansas. Map produced by the Kansas Weather Data Library.
Christopher “Chip” Redmond, Kansas Mesonet Manager
christopherredmond@ksu.edu
Mary Knapp, Assistant Climatologist
mknapp@ksu.edu
Tags: weather precipitation