The Alley Index

7-Day Forecast

A rule-based forecast built from NWS weather, AHPS flow predictions where available, recent storm pulse behavior, and current river scoring.

Updated Aug 4, 6:03 PM EDT

Best Window

Tuesday looks like the best window so far: 100 (Excellent).

Tue

100 Excellent

95% confidence

live Alley Index snapshot

Wed

33 Average

55% confidence

recent flow trajectory dropping

Thu

25 Poor

52% confidence

recent flow trajectory dropping

Fri

0 Blown

52% confidence

incoming rain matched to recent pulse behavior

Sat

17 Poor

46% confidence - low

incoming rain matched to recent pulse behavior

Sun

18 Poor

43% confidence - low

incoming rain matched to recent pulse behavior

Mon

10 Poor

49% confidence - low

incoming rain matched to recent pulse behavior

Tuesday, Aug 4 river details 31 rivers

Cuyahoga River

excellent

346 CFS - 70.9 F - Clear

Confidence 95%

Oak Orchard Creek

excellent

885 CFS - 74.8 F - Clear

Confidence 95%

Irondequoit Creek

excellent

141 CFS - 70.7 F - Clear

Confidence 95%

Elk Creek

excellent

10.21 CFS - 55.6 F - Clear

Confidence 95%

Crooked Creek

excellent

4.44 CFS - 55.6 F - Clear

Confidence 95%

Chagrin River

good

57.4 CFS - n/a F - Clear

Confidence 95%

Vermilion River

good

21.7 CFS - n/a F - Clear

Confidence 95%

Walnut Creek

good

11.1 CFS - 78.8 F - Clear

Confidence 95%

Twenty Mile Creek

good

17.54 CFS - 55.6 F - Clear

Confidence 95%

Huron River

good

32.4 CFS - 79 F - Clear

Confidence 95%

Sandy Creek (Hamlin)

good

103 CFS - 77.4 F - Clear

Confidence 95%

Rocky River

good

73.2 CFS - 81.5 F - Clear

Confidence 95%

Conneaut Creek

poor

113 CFS - 73.8 F - Clear

Confidence 95%

Grand River

good

44.4 CFS - 82.4 F - Clear

Confidence 95%

Brandy Run

good

1.69 CFS - n/a F - Clear

Confidence 95%

Cattaraugus Creek

good

169 CFS - 80.8 F - Clear

Confidence 95%

Chautauqua Creek

good

16.3 CFS - n/a F - Clear

Confidence 95%

Black River

good

14.6 CFS - n/a F - Clear

Confidence 95%

Euclid Creek

good

11.1 CFS - n/a F - Clear

Confidence 95%

Canadaway Creek

good

9.88 CFS - n/a F - Clear

Confidence 95%

Cazenovia Creek

good

49 CFS - n/a F - Clear

Confidence 95%

Eighteenmile Creek (Niagara)

fair

982 CFS - 70.7 F - Muddy

Confidence 95%

Ashtabula River

poor

88.48 CFS - 54.3 F - Clear

Confidence 95%

Eighteen Mile Creek

good

14.1 CFS - n/a F - Clear

Confidence 95%

Silver Creek

good

2.97 CFS - n/a F - Clear

Confidence 95%

Buffalo Creek

good

44.6 CFS - n/a F - Clear

Confidence 95%

Salmon River

good

260 CFS - n/a F - Clear

Confidence 95%

Genesee River

good

791 CFS - 73.2 F - Clear

Confidence 95%

Johnson Creek

fair

991 CFS - 71.4 F - Muddy

Confidence 95%

Sandy Creek (Adams)

fair

127 CFS - n/a F - Clear

Confidence 95%

Black River (Watertown)

fair

1450 CFS - n/a F - Clear

Confidence 95%

Wednesday, Aug 5 river details 31 rivers

Ashtabula River

excellent

168.2 CFS - 55.9 F - Stained

Confidence 56.7%

Cuyahoga River

excellent

467 CFS - 72.7 F - Stained

Confidence 68.8%

Conneaut Creek

good

145.4 CFS - 75.8 F - Stained

Confidence 56.7%

Irondequoit Creek

good

94.6 CFS - 72.9 F - Clear

Confidence 57.9%

Elk Creek

good

7.2 CFS - 58 F - Clear

Confidence 57.9%

Twenty Mile Creek

good

12.3 CFS - 57.5 F - Clear

Confidence 57.9%

Crooked Creek

good

3.1 CFS - 57.7 F - Clear

Confidence 57.9%

Oak Orchard Creek

good

500.5 CFS - 77.1 F - Clear

Confidence 57.9%

Johnson Creek

fair

1197.2 CFS - 73.1 F - Muddy

Confidence 56.7%

Sandy Creek (Adams)

good

80 CFS - n/a F - Clear

Confidence 49.9%

Rocky River

fair

62.2 CFS - 83.3 F - Clear

Confidence 57.9%

Chagrin River

fair

25.9 CFS - n/a F - Clear

Confidence 49.9%

Vermilion River

fair

15.5 CFS - n/a F - Clear

Confidence 49.9%

Canadaway Creek

fair

5.8 CFS - n/a F - Clear

Confidence 49.9%

Salmon River

fair

250.1 CFS - n/a F - Clear

Confidence 49.9%

Genesee River

fair

556.9 CFS - 75.8 F - Clear

Confidence 57.9%

Sandy Creek (Hamlin)

fair

52.9 CFS - 80.2 F - Clear

Confidence 57.9%

Black River (Watertown)

fair

1275.3 CFS - n/a F - Clear

Confidence 49.9%

Grand River

fair

34.8 CFS - 84.2 F - Clear

Confidence 70%

Brandy Run

fair

1.1 CFS - n/a F - Clear

Confidence 49.9%

Walnut Creek

fair

8 CFS - 80.1 F - Clear

Confidence 57.9%

Cattaraugus Creek

fair

160 CFS - 82.3 F - Clear

Confidence 70%

Chautauqua Creek

fair

12.5 CFS - n/a F - Clear

Confidence 49.9%

Eighteen Mile Creek

fair

8.2 CFS - n/a F - Clear

Confidence 49.9%

Black River

fair

9.3 CFS - n/a F - Clear

Confidence 49.9%

Euclid Creek

fair

10.3 CFS - n/a F - Clear

Confidence 49.9%

Silver Creek

fair

1.2 CFS - n/a F - Clear

Confidence 49.9%

Buffalo Creek

fair

31.6 CFS - n/a F - Clear

Confidence 49.9%

Cazenovia Creek

fair

28.4 CFS - n/a F - Clear

Confidence 49.9%

Eighteenmile Creek (Niagara)

poor

580.9 CFS - 71.4 F - Muddy

Confidence 56.7%

Huron River

fair

35.5 CFS - 81.1 F - Clear

Confidence 56.7%

Thursday, Aug 6 river details 31 rivers

Ashtabula River

fair

415.1 CFS - 55.5 F - Stained

Confidence 51.8%

Conneaut Creek

excellent

207.4 CFS - 75.1 F - Stained

Confidence 51.8%

Eighteenmile Creek (Niagara)

fair

276.6 CFS - 71.1 F - Muddy

Confidence 51.8%

Cuyahoga River

good

313 CFS - 72.3 F - Clear

Confidence 69%

Elk Creek

good

4.2 CFS - 57.5 F - Clear

Confidence 53.1%

Twenty Mile Creek

good

7.3 CFS - 57.1 F - Clear

Confidence 53.1%

Crooked Creek

good

1.8 CFS - 57 F - Clear

Confidence 53.1%

Oak Orchard Creek

good

223.6 CFS - 76.9 F - Clear

Confidence 53.1%

Johnson Creek

fair

1563.2 CFS - 73 F - Muddy

Confidence 51.8%

Chagrin River

fair

8 CFS - n/a F - Clear

Confidence 46.1%

Walnut Creek

fair

4.8 CFS - 79.8 F - Clear

Confidence 53.1%

Canadaway Creek

fair

2.5 CFS - n/a F - Clear

Confidence 46.1%

Genesee River

fair

1179.6 CFS - 75.1 F - Stained

Confidence 54%

Sandy Creek (Hamlin)

fair

20.3 CFS - 79.7 F - Clear

Confidence 53.1%

Irondequoit Creek

fair

567.9 CFS - 72.5 F - Muddy

Confidence 54%

Black River (Watertown)

fair

1063.8 CFS - n/a F - Clear

Confidence 46.1%

Sandy Creek (Adams)

fair

41.5 CFS - n/a F - Clear

Confidence 46.1%

Vermilion River

fair

98.2 CFS - n/a F - Muddy

Confidence 47%

Grand River

fair

24 CFS - 83.8 F - Clear

Confidence 69%

Brandy Run

fair

0.5 CFS - n/a F - Clear

Confidence 46.1%

Chautauqua Creek

fair

8.5 CFS - n/a F - Clear

Confidence 46.1%

Eighteen Mile Creek

fair

3.6 CFS - n/a F - Clear

Confidence 46.1%

Euclid Creek

fair

9.3 CFS - n/a F - Clear

Confidence 46.1%

Buffalo Creek

fair

19.3 CFS - n/a F - Clear

Confidence 46.1%

Cazenovia Creek

fair

12.9 CFS - n/a F - Clear

Confidence 46.1%

Salmon River

fair

268.9 CFS - n/a F - Clear

Confidence 47%

Rocky River

fair

149 CFS - 82.9 F - Muddy

Confidence 54%

Cattaraugus Creek

fair

160 CFS - 81.9 F - Clear

Confidence 69%

Huron River

fair

33.3 CFS - 80.4 F - Clear

Confidence 54%

Black River

fair

437 CFS - n/a F - Muddy

Confidence 47%

Silver Creek

fair

0 CFS - n/a F - Clear

Confidence 46.1%

Friday, Aug 7 river details 31 rivers

Oak Orchard Creek

good

1149.9 CFS - 76 F - Stained

Confidence 53%

Cuyahoga River

good

387 CFS - 71.5 F - Stained

Confidence 66.8%

Sandy Creek (Hamlin)

good

112.7 CFS - 79 F - Clear

Confidence 53%

Genesee River

good

1074.1 CFS - 74 F - Stained

Confidence 53%

Irondequoit Creek

fair

495.4 CFS - 71.4 F - Muddy

Confidence 53%

Black River (Watertown)

good

1788.3 CFS - n/a F - Stained

Confidence 47%

Conneaut Creek

fair

431 CFS - 74.5 F - Muddy

Confidence 53%

Twenty Mile Creek

fair

188.1 CFS - 56.5 F - Muddy

Confidence 53%

Crooked Creek

fair

27.6 CFS - 56.4 F - Muddy

Confidence 53%

Ashtabula River

fair

363.3 CFS - 54.7 F - Muddy

Confidence 53%

Elk Creek

fair

87.3 CFS - 56.6 F - Muddy

Confidence 53%

Walnut Creek

fair

74.6 CFS - 79.2 F - Muddy

Confidence 53%

Salmon River

fair

266.5 CFS - n/a F - Clear

Confidence 47%

Brandy Run

fair

8.5 CFS - n/a F - Muddy

Confidence 47%

Cattaraugus Creek

fair

226 CFS - 80.9 F - Stained

Confidence 66.8%

Chautauqua Creek

fair

69.5 CFS - n/a F - Muddy

Confidence 47%

Huron River

fair

33.6 CFS - 80 F - Clear

Confidence 53%

Silver Creek

fair

4.3 CFS - n/a F - Stained

Confidence 47%

Cazenovia Creek

fair

89.2 CFS - n/a F - Muddy

Confidence 47%

Johnson Creek

poor

6031.2 CFS - 72.3 F - Muddy

Confidence 53%

Eighteenmile Creek (Niagara)

poor

4229.1 CFS - 70.4 F - Muddy

Confidence 53%

Rocky River

poor

144 CFS - 82.3 F - Muddy

Confidence 53%

Grand River

poor

10.8 CFS - 83.2 F - Clear

Confidence 68%

Euclid Creek

poor

11.5 CFS - n/a F - Clear

Confidence 47%

Buffalo Creek

poor

99 CFS - n/a F - Muddy

Confidence 47%

Chagrin River

poor

1071.9 CFS - n/a F - Muddy

Confidence 47%

Vermilion River

poor

88.5 CFS - n/a F - Muddy

Confidence 47%

Black River

poor

486 CFS - n/a F - Muddy

Confidence 47%

Canadaway Creek

poor

37.3 CFS - n/a F - Muddy

Confidence 47%

Eighteen Mile Creek

poor

29.9 CFS - n/a F - Muddy

Confidence 47%

Sandy Creek (Adams)

poor

697.3 CFS - n/a F - Muddy

Confidence 47%

Saturday, Aug 8 river details 31 rivers

Conneaut Creek

fair

421.1 CFS - 74.4 F - Stained

Confidence 42.1%

Cuyahoga River

good

349 CFS - 71.8 F - Clear

Confidence 65.8%

Irondequoit Creek

good

16.9 CFS - 71.9 F - Clear

Confidence 43.4%

Genesee River

good

125.5 CFS - 74.5 F - Clear

Confidence 43.4%

Ashtabula River

poor

2513.9 CFS - 54.8 F - Stained

Confidence 42.1%

Elk Creek

good

1.1 CFS - 56.5 F - Clear

Confidence 43.4%

Twenty Mile Creek

fair

116.3 CFS - 56.2 F - Muddy

Confidence 52%

Crooked Creek

fair

16.4 CFS - 56.5 F - Muddy

Confidence 52%

Huron River

good

52 CFS - 80.3 F - Stained

Confidence 42.1%

Oak Orchard Creek

good

44 CFS - 76.3 F - Clear

Confidence 43.4%

Eighteenmile Creek (Niagara)

fair

62.2 CFS - 70.8 F - Muddy

Confidence 42.1%

Black River (Watertown)

good

1648.3 CFS - n/a F - Stained

Confidence 47%

Vermilion River

fair

3.3 CFS - n/a F - Clear

Confidence 38.4%

Sandy Creek (Hamlin)

fair

2.3 CFS - 79.2 F - Clear

Confidence 43.4%

Rocky River

fair

31 CFS - 82.6 F - Clear

Confidence 43.4%

Walnut Creek

fair

46.8 CFS - 79.8 F - Muddy

Confidence 52%

Chautauqua Creek

fair

50 CFS - n/a F - Muddy

Confidence 47%

Black River

fair

0.7 CFS - n/a F - Clear

Confidence 38.4%

Euclid Creek

fair

7.6 CFS - n/a F - Clear

Confidence 38.4%

Silver Creek

fair

3.6 CFS - n/a F - Stained

Confidence 47%

Salmon River

fair

266.4 CFS - n/a F - Clear

Confidence 47%

Johnson Creek

poor

2664.9 CFS - 72 F - Muddy

Confidence 42.1%

Chagrin River

fair

0 CFS - n/a F - Clear

Confidence 38.4%

Grand River

fair

-999000 CFS - 83.3 F - Clear

Confidence 67%

Brandy Run

fair

5.1 CFS - n/a F - Muddy

Confidence 47%

Cattaraugus Creek

fair

174.4 CFS - 81.3 F - Clear

Confidence 52%

Cazenovia Creek

fair

76.3 CFS - n/a F - Muddy

Confidence 47%

Canadaway Creek

poor

28 CFS - n/a F - Muddy

Confidence 47%

Buffalo Creek

poor

81.6 CFS - n/a F - Muddy

Confidence 47%

Sandy Creek (Adams)

poor

487.4 CFS - n/a F - Muddy

Confidence 47%

Eighteen Mile Creek

poor

24.5 CFS - n/a F - Muddy

Confidence 47%

Sunday, Aug 9 river details 31 rivers

Irondequoit Creek

good

9.3 CFS - 71.4 F - Clear

Confidence 38.5%

Conneaut Creek

fair

228 CFS - 74.5 F - Muddy

Confidence 51%

Cuyahoga River

good

100.1 CFS - 71.7 F - Clear

Confidence 38.5%

Genesee River

good

76.1 CFS - 74.2 F - Clear

Confidence 38.5%

Ashtabula River

fair

176.1 CFS - 54.8 F - Muddy

Confidence 51%

Elk Creek

fair

59.4 CFS - 56.6 F - Muddy

Confidence 51%

Twenty Mile Creek

fair

122.3 CFS - 56.3 F - Muddy

Confidence 51%

Crooked Creek

fair

19.2 CFS - 56.6 F - Muddy

Confidence 51%

Huron River

good

59.1 CFS - 80.2 F - Stained

Confidence 37.3%

Oak Orchard Creek

good

19.2 CFS - 75.8 F - Clear

Confidence 38.5%

Eighteenmile Creek (Niagara)

fair

29.1 CFS - 70.6 F - Muddy

Confidence 37.3%

Black River (Watertown)

good

1597 CFS - n/a F - Stained

Confidence 47%

Vermilion River

fair

1.8 CFS - n/a F - Clear

Confidence 34.5%

Walnut Creek

fair

52.3 CFS - 79.6 F - Muddy

Confidence 51%

Sandy Creek (Hamlin)

fair

0.3 CFS - 78.8 F - Clear

Confidence 38.5%

Rocky River

fair

24.5 CFS - 82.5 F - Clear

Confidence 38.5%

Grand River

fair

19.1 CFS - 83.6 F - Clear

Confidence 38.5%

Chautauqua Creek

fair

52.1 CFS - n/a F - Muddy

Confidence 47%

Euclid Creek

fair

6.8 CFS - n/a F - Clear

Confidence 34.5%

Silver Creek

fair

3.3 CFS - n/a F - Stained

Confidence 47%

Salmon River

fair

266 CFS - n/a F - Clear

Confidence 47%

Johnson Creek

poor

3479.3 CFS - 71.8 F - Muddy

Confidence 37.3%

Chagrin River

fair

0 CFS - n/a F - Clear

Confidence 34.5%

Brandy Run

fair

5.9 CFS - n/a F - Muddy

Confidence 47%

Cattaraugus Creek

fair

176 CFS - 81 F - Clear

Confidence 51%

Black River

fair

0 CFS - n/a F - Clear

Confidence 34.5%

Cazenovia Creek

fair

78.9 CFS - n/a F - Muddy

Confidence 47%

Canadaway Creek

poor

30.2 CFS - n/a F - Muddy

Confidence 47%

Buffalo Creek

poor

85.1 CFS - n/a F - Muddy

Confidence 47%

Sandy Creek (Adams)

poor

454.3 CFS - n/a F - Muddy

Confidence 47%

Eighteen Mile Creek

poor

26.1 CFS - n/a F - Muddy

Confidence 47%

Monday, Aug 10 river details 31 rivers

Oak Orchard Creek

good

1149.9 CFS - 75.6 F - Stained

Confidence 50%

Conneaut Creek

fair

256.8 CFS - 74.6 F - Muddy

Confidence 50%

Genesee River

good

930.9 CFS - 73.9 F - Stained

Confidence 50%

Sandy Creek (Hamlin)

good

106.3 CFS - 78.6 F - Clear

Confidence 50%

Irondequoit Creek

fair

391.2 CFS - 71.3 F - Muddy

Confidence 50%

Ashtabula River

fair

208.9 CFS - 54.9 F - Muddy

Confidence 50%

Cuyahoga River

fair

598 CFS - 71.9 F - Muddy

Confidence 50%

Elk Creek

fair

71.3 CFS - 56.4 F - Muddy

Confidence 50%

Twenty Mile Creek

fair

158.2 CFS - 56.2 F - Muddy

Confidence 50%

Crooked Creek

fair

22.8 CFS - 56.5 F - Muddy

Confidence 50%

Black River (Watertown)

good

1597 CFS - n/a F - Stained

Confidence 47%

Walnut Creek

fair

63.5 CFS - 79.7 F - Muddy

Confidence 50%

Brandy Run

fair

6.9 CFS - n/a F - Muddy

Confidence 47%

Chautauqua Creek

fair

64.4 CFS - n/a F - Muddy

Confidence 47%

Silver Creek

fair

3.4 CFS - n/a F - Stained

Confidence 47%

Salmon River

fair

267 CFS - n/a F - Clear

Confidence 47%

Rocky River

fair

127.8 CFS - 82.5 F - Muddy

Confidence 50%

Grand River

fair

46.1 CFS - 83.4 F - Clear

Confidence 50%

Cattaraugus Creek

fair

177.4 CFS - 81.2 F - Clear

Confidence 50%

Huron River

fair

33.3 CFS - 80.3 F - Clear

Confidence 50%

Black River

fair

378.5 CFS - n/a F - Muddy

Confidence 47%

Euclid Creek

fair

11.4 CFS - n/a F - Clear

Confidence 47%

Cazenovia Creek

fair

86.6 CFS - n/a F - Muddy

Confidence 47%

Johnson Creek

poor

5088.2 CFS - 71.7 F - Muddy

Confidence 50%

Eighteenmile Creek (Niagara)

poor

4229.1 CFS - 70.6 F - Muddy

Confidence 50%

Chagrin River

poor

693.6 CFS - n/a F - Muddy

Confidence 47%

Vermilion River

poor

73 CFS - n/a F - Muddy

Confidence 47%

Canadaway Creek

poor

35.7 CFS - n/a F - Muddy

Confidence 47%

Buffalo Creek

poor

95.5 CFS - n/a F - Muddy

Confidence 47%

Sandy Creek (Adams)

poor

499.7 CFS - n/a F - Muddy

Confidence 47%

Eighteen Mile Creek

poor

29 CFS - n/a F - Muddy

Confidence 47%

Methodology

This is a deterministic forecast, not an AI prediction. Flow uses AHPS when available, then storm pulse signatures, then recent log-linear flow trajectory, then a flat baseline fallback. Temperature and clarity are conservative heuristics. Confidence drops as the horizon gets farther out, especially on days 5-7.