What are my chances

Hi,
I’m a junior in high school. As a junior I am taking all honors/AP classes except for 1. However, for my first semester of junior year, I got really bad grades (including a C) because it was my first time taking so many APs. Next semester, I do plan on significantly improving my grades. I have taken a SAT and got 1300 and am looking forward to retakes for a higher score.
For my extracurriculars, I’ve made it to a national leveled competition for cyber security, help run a cyber security program at my school by teaching other students, founded a 2 non-profit clubs and 1 international non-profit organization, and am currently a board member for another non-profit club at school.
My school is considered pretty competitive (Ranked one of the top public schools) and I’m wondering what are my chances I can get into a school like UCSD or other UCs.
Furthermore,
-I’m thinking about majoring in computer science
-During my freshman and sophomore year I obtained a 4.3 GPA

UC’s use only 10-11th grades in their GPA calculation. Freshman grades are reviewed to make sure the a-g course requirements are completed. Senior grades will help you maintain your provisional admission but not considered for admission purposes.

Here is UC GPA calculator. Most of the GPA information posted is based on the cappedcweighted UC GPA but the fully weighted GPA is considered by the top campuses.

https://rogerhub.com/gpa-calculator-uc/

CS is highly competitive so once you have your UC GPA calculated and test scores, you should be able to determine your chances better.

Some statistical data for comparison based on capped weighted UC GPA and not major specific. Competitive majors would require higher stats with lower admit rates:

Freshman admit rates for UC GPA of 3.40-3.79:

UCB: 1.8%
UCLA: 2.2%
UCSD: 7.2%
UCSB: 10.1%
UCI: 11.1%
UCD: 16.6%
UCSC: 43.8%
UCR: 63.3%
UCM: 88.7%

Freshman admit rates for UC GPA of 3.80-4.19:

UCB: 12.6%
UCLA: 11.7%
UCSD: 38.7%
UCSB: 53.6%
UCD: 56.5%
UCI: 52.1%
UCSC: 75.7%
UCR: 90.1%
UCM: 96.1%

Freshman admit rates for UC GPA of 4.20 or above:

UCB: 42.7%
UCLA: 47.2%
UCSD: 84.2%
UCSB: 82.0%
UCD: 90.3%
UCI: 94.1%
UCSC: 92.7%
UCR: 97.5
UCM: 98.1%

2018 UC capped weighted GPA averages:
UCB: 4.23
UCLA: 4.23
UCSD: 4.16
UCSB: 4.13
UCI: 4.13
UCD: 4.11
UCSC: 3.96
UCR: 3.81
UCM: 3.71

2018 Data:
25th - 75th percentiles for SAT:

UCB: 1360-1540

UCLA: 1340-1540
UCSD: 1300-1520
UCSB: 1270-1500
UCD: 1220-1480
UCI: 1230-1490
UCSC: 1210-1450
UCR: 1130-1380
UCM: 1020-1280

25th - 75th percentiles for ACT:
UCB: 30-35
UCLA: 31-35
UCSD: 28-34
UCSB: 28-34
UCD: 26-33
UCI: 26-33
UCSC: 26-32
UCR: 22-30
UCM: 19-26